So I've been thinking of buying a water heavy bag for my backyard to train on days the gym is closed. Any opinions on those Tsunami water bags from ringside?

http://www.ringside.com/Tsunami-Water-Bag-105lb/productinfo/TWB4/

it looks pretty reasonably priced, anyone have experience with these things?

Tsunami's look great, I've never tried them myself, but the ones I've used in the past were great. Much better for the hands/wrist/elbow/shoulders than the traditional heavybags. Water bags have a realistic feel to it, it almost feel like you're hitting a person.