I've had the Matuse 4/3/2 since just before Thanksgiving, so can give some thoughts on it. Can't say anything about the ECO, haven't surfed in it and it might be great. As far as perspective, I'm in the water about 300 days/yr., last fullsuit was RipCurl F-Bomb (loved it, abused it), had the PsychoII alongside that (loved it too, but the cut just doesn't work quite as well for my body - a personal thing).
Now, my two cents on the Matuse after having worn it for over two months in one of the coldest winters (water temps) we've had in San Diego county in years and through several great swells..
Good stuff:
Essentially for a 3/2 (the 4 is all on the chest and lower back so no paddle impact), it's the warmest, lightest and most flexible suit I've ever owned. Overall I love it and I actually found this thread because I'm now out trying to figure out how much the Matuse 2/2 Short Sleeve fullsuit and the spring suit are going to cost me because I'm definitely going to buy both. Somebody earlier in the thread said something about not liking wool - but I think that's the Patagonia. Nothing in the Matuse looks or feels like wool - I honestly don't think it has any. Anyway, in 54 degree water I find myself hopping into the water for a good flush to cool off after a few good waves - over 60 days of surfing and I've gotten downright hot in it every single time. By the way, that's why I'm looking for the Matuse 2/2 short sleeve fullsuit - I'm a little worried that the suit might be too warm once the temps get into the low/mid 60's. It's true what they say about the lack of water absorption and the lighter weight. I hang that thing in the garage and three hours later it is dry - while my booties are still wet the next day.
Bad stuff: There's this farmer john contraption inside that works very well but that I absolutely know is going to be the first material to rip because it is just so thin and flimsy. Hasn't torn yet, but I'm treating it uber-gentle every time I suit up. We all need a good key pocket in our fullsuit, and the Matuse just has one of those loop cords like in your trunks that is located inside the back of the suit near the back zipper - which means you can't get to your car key when your standing there in the cold next to your door until you unzip - not good.
Overall: I love the material. Feels great, lighter and more flexible than anything I've owned and I've pretty much owned anything I felt like trying out. I'm out trying to buy two more suits they make right now, that should say it. I wish they made booties and headgear.