I put together a similar comparison back in 2018, but it looks like those threads were archived or taken down. I think our opinions are very similar -- Arccos seemed to have easier setup and UI; Shot Scope has a leg up in post-round activity (e.g. no need to go back and place the holes), extra tags, and tag size; both offered similar stats with Arccos maybe being a bit better; I dislike both of the tracking systems (phone in pocket and big watch instead of my own watch), I never made it through 36 holes with either system, etc. I later tried Game Golf Pro, which did not work for me at all and I ultimately got them to refund it (thread also no longer exists?). I still have my Arccos sensors on the bench awaiting delivery of Link, hoping that gives a better experience. My actual preference would be a hybrid system where small tags integrate with my Garmin Fenix, but it looks like that's not on the roadmap (and I won't switch to an Apple Watch because I'm stubborn ) -- Garmin does offer sensors, but they only pair with certain watches, which excludes Fenix models .
I have an old draft of my original review, included below, in which I tried to categorize into things that matter to me offering a "winner" in each category. Similar to what you said, I didn't declare an overall preference because I don't really have one -- Arccos looks better on paper within the categories I picked, but I actually felt better with Shot Scope because of the tag size, especially on the putter (good news: Arccos said they will include a smaller putter sensor with my Link shipment!). I saw a thread advertising Shot Scope v3 with a much smaller, sleeker watch, but don't see that on their website at all - maybe that will eventually be the best product?
I'm a little late to this thread, but I've used both, so hopefully I can help. I used Arccos 360 for about a year, then switched over to Shot Scope v2 for the last couple months. They have had similar results, but there are definite pros/cons to each. It really comes down to personal preference -- right now, I prefer Shot Scope (mostly because of the tags), but I am considering giving Game Golf Pro a shot when it finally comes out in September (I switched to Shot Scope because of product delays with Game Golf, and there's no way I'm tapping before every shot like the old Game Golf requires). I'll separate them into a few categories that are important to me, giving a winner to each category:
***Important note: I made the switch without trying Arccos Caddie 2.0, so I don't what kind of improvements came with that.
Tracking Hardware: Toss-up. Arccos 360 requires a phone or similar device in your pocket; Shot Scope requires you wear their bulky (and ugly) watch. I'm not a fan of the phone in the pocket, especially the larger ones (I currently have a Pixel XL); as far as the watch goes, I normally wear my Garmin Fenix while playing, so the Shot Scope feel is fine with me, but I'd prefer to wear my normal watch (activity tracking, etc.). I've heard that Arccos is going to get rid of the phone-in-pocket requirement in the near future, but don't know when or how that is happening.
Tags: Shot Scope. This is the biggest deal for me. The Arccos tags are too big - they are noticeable as you grip the club (especially the putter tag, which is HUGE), and they add a counterweight to the club. Shot Scope's feel cheaper, but they are lower profile and lighter, so they don't get in the way as much as Arccos. If you want to track a different club, you need to reprogram your Arccos tag, while Shot Scope gives you a handful of extras.
Battery: Toss-up. Arccos drains my phone, especially if I do anything else with it, so I need to make sure it has a good charge before the round. Shot Scope seems to last 5-6 hours on a full charge. Neither would make it through 36 holes. I've heard reports that the Shot Scope watch battery drains when not in use, but I haven't seen that as an issue.
Software (General): Arccos. Both have a phone app providing sufficient functionality. Both have an online dashboard that shows more information than the app. The key difference is that Arccos can do almost everything in the phone app, while Shot Scope bounces between phone app, desktop app, and online dashboard to manage things.
Ease of Use - Startup: Arccos. With Shot Scope, you need to prepare courses in advance, first selecting courses then transferring to the watch. The transfer process is easy if you use the desktop app and cord, but wireless transfers are slow. With Arccos, you need to download the course to your phone, but I've done this many times on the first tee with no issue. Similarly, Arccos uses your phone's GPS, so it picks up location very quickly, while the Shot Scope watch sometimes takes a couple tries or a few minutes to figure out where you are (the last time I used it, it missed the entire first hole).
Ease of Use - Finishing the Round: Shot Scope. If you want accurate approach and short game stats with Arccos, you need to edit your round and place the hole location on each green (or do it from your phone mid-round), otherwise it just assumes center of the green. Shot Scope lets you do this on the course with the watch's PinCollect functionality, just pushing a button to mark the hole and the number of times you hit the putter.
Accuracy: Toss-up. Other accuracy data: Both seem to miss a similar number of shots. Both have picked up on movement that is not a swing (e.g. knocking sand off of my shoes after a bunker shot tagged a swing outside of the bunker). Neither have done all that well adjusting to knockdowns, punch shots, etc. Shot Scope asks you how many putts you have on each hole, while Arccos requires that you set up to every putt to track them (even then it misses some short ones), or just add the tap-ins later.
Statistics: Arccos (again, I have not used the new Arccos Caddie 2.0 features, so they may have even more to offer now). Most of the stats are comparable -- they both track actual distances and perform some analysis to give you true expected distances for the clubs; they both track proximity (as noted above, Shot Scope is more automated, Arccos is a bit of work); they both drill down into stats for specific clubs. Both have a good amount of statistics in the app, and both have better statistics on their web dashboard. The thing that gives Arccos the leg up is that they compare to other golfers (I assume) to assign handicaps, not just overall but also per category (and per round), which is useful information for game improvement (I haven't found similar Shot Scope functions). For example, it says I'm a 1.5 (actual index 2.8), but also shows that my approach shots are about scratch, while my sand skills are more in line with a 14. For round-by-round, in one round it says I hit approaches like a +4 but putted like a 30 handicap; in another, I drove it like a 13 but chipping and putting were close to scratch (both scores ending up roughly the same). It's not actionable data, just good to know.