Hi!
I also use Molicel batteries, 3 pairs (P28A) currently, with a Geekwape Z200 mod, and a Valyrian 3 tank. I have also used it with an RTA with 0.11 resistance. The youngest pair is also more than a year old, and the oldest is almost 2 years old. So far, I don’t feel any performance decrease. I can only recommend them too 
I can recommend the https://thebatteryshop.eu/hu website. Although there is a minimum order amount, the prices here are very good, and there is stock too