If I reviewed a water block, I wouldn't advance any ideas for improvement: I'd just stick to reviewing the block. Otherwise, I'd be more than happy to charge a consultant fee for my opinions.
This is the only kind of review that is really expensive to do, to my knowledge, because of all the work and equipment involved. When I build a testbench, you can bet I'm going to put it to good use.
The only issue I'm debating for myself, is what kind of position am I putting myself in, if I start making and selling a water block, while I review others? Obviously all the blocks are publicly available, so it shouldn't be a big deal, right? Bill reviewed blocks, and had testing services on the side, so I'd be doing something similar, no? :shrug: