Do you want one that looks like a cig?
If you dont care what it looks like a bigger battery PV is def the way to go.
Like swedishfish suggested, the E-Power and kGo are great affordable PVs that have great battery life. I have the E-Power and love it. It uses non-proprietary batteries and I get about a day to a day and a half on a single battery, and you get 2 with the kit so youd really never have to worry about running out of power. Carrying a spare is easy bc the battery is about the size of a AA but alittle longer. The kGo is also a great PV that has long battery life too. It really depends what your looking for. The kGo uses proprietary batteries, like an eGo/Riva. The E-Power batteries cost $4, and the kGo batteries cost about $18. So its whatever your looking for, both are great. I personally liked that I could take the battery out of the E-Power so its easy to carry a backup with you. The kGo kit comes with 2 batteries also, but since their proprietary batteries, you basically have to carry a 2nd PV with you without a atty/carto on it to carry a second battery, which if that doesnt bother you then its def a great PV that has good battery life. The E-Power batteries are 1050mah while the kGo batteries are 1100mah, so both should be able to last you the whole day.
There are also a bunch of really nice tube mods. These use non-proprietary batteries like the E-Power.
Like someone mentioned the Roughstack. Thats a good tube mod thats only about $45 bucks. The regular Roughstack is pretty small and seems to hold up really well. If you get the Maxi RoughStack, while their alittle bigger, you can use different batteries and then would be able to vape at 3.7V, 6V, or 7.4V. If you get the RoughStack, id recommend getting the High-Drain batteries. They are alittle more expensive, but def worth it. The RS is unregulated so you will loose power as the battery drains. The High-Drains stay more consistant so you wont notice as big of a drop as the battery drains.
The SilverBullet is also a popular tube mod that uses non-proprietary batteries and can use different batteries for different voltages like the MaxiRS, but it is bigger than the RS. Its more expensive than the RS but I heard it holds up well and doesnt cause problems very often.
Personally I like the PVs that use non-proprietary batteries over a PV that uses prorietary batteries because their much cheaper and last longer before they need to be replaced, and its easy to carry a spare so youll never have to really worry about a dead PV.
There are many tube mods that are affordable. Many use the popular 18650 battery and youd prob really like one of those bc they have great battery life. The 18650 batteries are pretty cheap and many many vendors carry them.
With most of the tube mods, like the E-Power, Roughstack, and many others, you can get High-Drain batteries for them, which is nice to have that option.
If your willing to spend alittle more, theres some really nice VV tube mods that are popular. Obviously the Provari is really nice, but its also expensive and not everyone has the money to afford that, You can get a InfinityPro or BuzzPro from Notcigs and have a really nice VV tube mod that is a good bit cheaper than the Provari. The IPro is about $100, while the BuzzPro is about $130. Both are really nice and use non-proprietary batteries, that will give you good battery life. They also both have a dial so you can change the voltage easily. Youd be able to use pretty much any ohm carto/atty bc you could just dial it in to the perfect vape for you. Both also give you the option of choosing between different threadings for them so you could get what you want.
The IPro is skinnier and longer, while the BuzzPro is alittle shorter, but fatter.
Hope this helped!
Goodluck with it!
For what it is and how cheap they are they're awesome. If you get the kgo and a 510-901 (Mistic is 808) you can use the mistic cartos on the kgo if you wanted to.
