I wouldn't. The only way I'd even consider it would be if it were:
1) a very well designed database
2) searchable by many criteria
3) packed with the contents of many, many OGL sources
4) full of with color print-resolution images
5) continuously updated (say, monthly) with new data for at least a year.
I'm constantly thinking things like, "OK, so the Ice Vampire has created a bunch of flying-monkies. I wish I had a cold-based undead creature that can fly. It should be small or medium-size, humanoid, and about CR 7 or 8." I've seen some online databases like this, but they're rarely updated, usually core-only, not fully-functional searches, etc.
Spider