I've been gaming a Cure RX2 (like the one in the OP pic), for just over a year now and I will say it is far and away the best putter I have ever had.
I've never had the perfect putting stroke, but the RX2 has helped tremendously - It is unbelievably stable because it has a ridiculously high MOI. It also is basically impossible to mishit a putt with this putter which has made me much more consistent, especially on longer putts. When I was first testing it out, the guy showing it to me had me roll a few putts to a hole about 15 feet away and then he told me to hit a few all the way off the toe with the same stroke - it still felt really solid, rolled straight on line and the first one actually went in, with the other stopping close by. I then took some longer putts 30-40 feet and I was consistently tight around the hole. The feel, forgiveness and distance control with this putter are something I have never experienced. I bought it on the spot and it went in the bag to stay.
As for the adjustability - it has a huge range of weighting options - starting at 371 grams, you can add weight in small increments all the way up to 582g. The great thing here is that because of the way the weights attach off the back, it makes a number of combinations possible - I think most other weight adjustable putters have a 20-30 gram window because you take a light weight out and replace it with a heavier weight or vise versa, but you only have 1 weight in the heel and 1 in the toe - I can have no weight, 1 weight or multiple weights, aluminum or stainless to achieve any weight I want and find what works best. As I spent some time with the putter, I began adding a little more weight from time to time during practice. I finally settled at 476g with a MOI of 15,200. I know that sounds really heavy, but that's the magic number for me. Maybe not for you, but with everything off the rack topping out at 400g, you may never know if a heavier weight actually works better with your stroke.
I have become a big believer in High MOI putters as the stability and forgiveness makes such a big difference for a guy like me - but to put it in perspective, (I think) the highest MOI mallet out there is the TM Daddy long legs 395g / 8500 MOI - My Cure RX2 at the same weight = 395g / 11,700 MOI - My current set up = 476g / 15,200 - Do the math...pretty significant.
I have tried out a ton of High MOI mallets over the years and owned several - Trust me this is another level.
With a typical putter, I generally agree with several of the posts above - that you need to know what your doing to "fit" a putter and that the lie should only be set once etc... However, there's a little more to the story with this putter. First, I agree that you should not always be tinkering too much, butI will say that I have enjoyed being able to adjust my lie a bit flatter once or twice over the past year, and since you can just loosen a few screws, adjust and tighten them back down, there's no risk, you can always adjust it back. I don't need an expert to tell me where my hands are comfortable. The other really cool thing is that the shafts are not only adjustable, but interchangeable... After a few months of having the putter, I went on their website and saw that they offered an offset shaft which intrigued me. I called them and ordered one ( $49 with a grip) and popped it right in and reset my lie angle in a matter of minutes and was off to the practice green. I ended up liking the offset shaft even better, but I always have the opportunity to switch back later if I want.
So basically you can get a custom fit and set up exactly how you want it, with the ability to change weight, shifts, lie etc
It has really high MOI - stable and forgiving, better distance control and did I mention that it rolls GREAT!
The looks may not be for everyone - people will say things, your buddies will make fun of you at the beginning of the round, start asking questions before the turn and want to try it by the end - More than a couple of the guys I play with picked one up after trying mine. For me, it didn't take long to get used to looking down at it - seeing an immediate improvement didn't hurt either - beauty is in the eye off the beholder. If you can get your hands on one and start making more putts, I bet you'll think it's a gorgeous as I do.
There's a lot more info on their website and a few new models worth checking out, a smaller heel shafted version and a more traditional style, oversized blade with High MOi which is very interesting and may appeal more to some.