I've been vaping an R5 XL Clear Cartomizer, (someone on another thread dubbed them Clearo's, and I like that), for almost 2 weeks. Prior to this I vaped Steel R4 XL's. I find the R5 Clearo much improved. Wicking appears to be improved. However, mine, it helps to vape horizontal, or even Batt high. This is pretty normal attitude for me anyway. I vape 50/50 or greater % VG juice. Differences I notice between the R4's and R5's are: it wicks better, and, (maybe because it's plastic), the Clearo doesn't get as hot. My R4's, (metal), got very hot, depending on the juice I vaped. Another difference, the R5 XL appears to be a juice hog. Either that, or I enjoy it so much that I've increased my vaping from 2 XL's a day to neigh onto being through a third fill. Mine are 2.6~2.8 ohm, clear. I can see some might use the translucent colored versions for juice differentiators, or even different colors in different ohm ranges. Lots of possibilities. The Clearo is a winner for me. JMHO
Cheers,
otrpu