Picked the 1TB version up as a replacement to the LaCie Rugged that I purchased with my Mac a while ago that failed shortly after. It has performed far better than I had hoped, has not failed, and isn't even half full after nearly three years of use as a Time Capsule.
I'd highly recommend this in any size, especially over anything LaCie.
I have had this drive now for a month and have had zero problems, and have had it as a movie storage drive for the home network so it gets used quit a bit and has worked flawlessly! have had it hooked up to my mb pro with lion and have had no problems there either would recommend to anyone.