I agree with 99.99% of what you say. Suzan was definitely good in bed but I'd personally put Masha a little bit ahead of her. It might be a personal preference though. As opposed to Kami being the worst female lover on RLC, I'd put Masha as the best female lover ever on RLC.
Iris is a godsend in the sexual department on VV. She's a little skinny for my tastes but she's so sexy I would still pick her over every other girl on VV, and most girls on RLC.