I agree with Kirsty - Emma is fab at customising nappies to suit your LOs wetting. Ours stand up well against my heavy wetter. And I'd also avoid anything with MF in (like Bedbugs or standard Hollow Oaks, although the ones I have with zorb work OK for Iris). I've recently found that BubuBébé work quite well for Iris. I do a complex fold with all the layers which means a stoopid amount of fabric in the wet zone, but it lasts! Dunk N Fluff are definite firm favourites, again because of how I can fold the boosters to make more fabric in the wet zone. Otherwise I just boost with a ton of hemp or bamboo. And you can boost between nappy and wool, if putting too much boosting in the nappy leads to leg gape.
Iris managed to outpee a nappy t'other day in under 3 hours - there was literally a river running down her legs, poor little thing was distraught. I try to change her more frequently, but just forgot.
It's a pain having a heavy wetter.
ETA: When you say you emailed Emma with weights, do you mean of a wet nappy? That's what I did.