Im using a DIY one using Glade plastic container. It looks fine and cheap to assemble too.

inside or outside reservoir?

Apogee GT review up

http://www.pcmoddingmy.com/e107_plugins/co...p?content.408.1
included are instructions on how to bow the base.
gave a serious boost.

try it and report back how did urs go...

Well I don't know if anyone "swears by it", but its is popular simply because it is cheap and it works. It is actually extremely similar to the Hydor Seltz L20 pump (it might be made by the same ppl or maybe not, knowing china peeps for making copies of other products.)
Nevertheless, quite a few ppl use it here for budget water cooling. It has reasonable amount of max head, approx 1.8-2 m (box and pump sticker stays different figures LOL), which is good enough for not too restrictive loops.
The downside, is lower reliability than well known pumps like the Laing D5. over time it can make some clicking sounds, but not loud in my experience. And then, it makes louder noises... a sign that it's probably deteriorating (hearing from user experiences). Typical lifespan probably 1-2 years? That you need to ask the users on this board as I don't use this pump a whole lot.