Just to caution you about Provape's 510-eGo thread adaptor. There have been at least a couple of threads here their adaptor not working with certain eGo delivery devices. Some people have argued that theirs has not worked, others have said that theirs does. Very confusing. I don't know myself, as I don't own one purchased from Provape.
Concerning the 18490 battery, if I put a fresh one in in the morning, it will last me until around 7 - 8 PM. With an 18650, it would last me until bedtime around 11 pm.