Hello. I'm trying to find replacement coils for my smoktech Pyrex mbc v1, so I FINALLY found a website. It is asking me for resistance options. 1.4-4.0. Idk which one to order because idk the difference. It came w a 1.8 ohm coil. I went to a local smoke shop and they said I should try a 2.5 ohm coil. Issue is the threading is a little off so my mvp doesn't always recognize it. So, mum thing is what is the difference with the resistance. Please help.