What are the WORST diapers you've ever used?

I'm part of a research team that needs to collect pee from babies. We are having a lot of problems with diapers that wick away the pee too fast, so we can't collect it. So I'd love to hear about the LEAST absorbent diapers you've ever used. Gimme leaks, gimme blowouts, gimme your terrible diaper recommendations!

EDIT: Thank you so much for all the replies everyone! I'm compiling a list and we'll be ordering a bunch of different brands to test absorbency (maybe I'll even post the results here)!

I got a lot of comments from people recommending we put cotton in the diaper, and this is actually what we do! We put a small strip of cotton between the baby and the diaper and then (try to) squeeze out the urine with a syringe. We have not had a high degree of success with this because the diaper wicks the urine away from the cotton if we don't change the diaper quickly enough. If anyone who uses this technique has any advice on how to improve success, I'm definitely open to hearing it!