NO, saturn is talking about blu, revolver, volcano... expensive e-cigs the size of a cigarette. Now may be a good time to learn about mah.
Every battery has a "mah" rating which is basically a rating that tells you about how long the battery will last between charges. For every 100mah you can expect about an hour of use (depending on how much you use it, but that's near the average).
the standard 510 = 180 mah (1-2 hours)
the mega 510 = 280 mah (3-4 hours)
the standard 808 = 280 mah (3-4 hours)
the xl 808 = 380 mah (4-6 hours)
the eGo = 650 mah (6.5-8 hours or so)
the mega eGo (or eGo XL) = 1000 mah (10-14 hours or so)
If you get anything less that 650mah I would recommend that you also get the PCC to go with it, unfortunately I don't think that they make a PCC for the 808 XL batteries, so with two of them in a kit you'll either want to be home within 10 hours or carry around your charger, or get extra batteries. IMO.