The manual battery is what enticed me to first try a 510. I got so tired of 901 and 801 auto batteries as they were nothing but trouble for me. I will never go back to an auto switch.
My only drawback for the 510s are the short battery life, though I have so far, never had a 510 battery fail on me. (knock on Wood) I do so love the vapor production from my 510s.
I would however like to try a 901 and or an 801 manual.
That would be cool.
Edit: I forgot all about the Kissbox. LOL. I just never considered buying one just because of the price. The Kissbox is not actually a manual battery, it is a non switched battery. That's why it didn't come to mind.