I've heard all positive reviews on the EWA-Marine SLR cases - and those are universal for SLRs so it'll work with either your 20d or 300d (both dSLR's, right?).
I'm still trying to decide between the U-FX and the U-AX... one is designed to allow manual focus (F) and the other is only for auto focus (A)... but I think I need to email EWA to get full information on both.
-Steve |