Sorry, I didn't notice your message yesterday. Anyway the MKII works great with a 510 adapter. As for which one I prefer, that's a hard question. I love the Tornado with Nhalers LR attys but I still find myself using the MKII when I'm home. If I had to just pick one I'd have to go with the Tornado just because it's a little smaller and more descreet. Just make sure to get some LR attys from Nhaler. Hope this helps.