I just recently bought the Dewalt cordless/corded model which you're asking about. As far as suction goes, it's ok for small cleanups. It's pretty decent considering it's size.
The reason I bought this was because I was tired of lugging my Rigid wet/dry vac for small jobs and in small areas. This is where the Dewalt comes in extremely handy. And it sucks water really well! And it's got a neat drain plug so you don't have to open it up just to drain it out.
I have to say I'm pretty impressed with this vacuum despite it's price. I'd recommend it.