Hi Jacqui-
I agree with Helen. If you want to try a different model, you should try an eGo (also known as a Tornado). If you act fast you can get one from
The Electronic Cigarette Company for 50% off (sale ends at the end of the month or until they sell out). The model you have has very small batteries in comparison, and getting 2 hours out of them sounds about right. The larger batteries on the eGo/Tornado will last considerably longer.
If you feel that you need something that looks and feels like a cigarette, the Titan (available from the same link) is a good alternative. It uses the same 510 atomiser (which runs hot and produces a lot of vapor), but the batteries are still small and will only last a few hours. That is the trade-off that we all live with.
You may also want to check your inhalation technique. If you take short, sharp, strong inhales then you won't get a lot of vapor. You need to take a very long, slow inhale that matches the same constant speed of the atomiser vaporizing the juice. And if your model has an automatic battery (one that turns on when you inhale, as opposed to one with a button) it helps to take 1-2 quick puffs followed immediately by a long, slow inhale to get it going. You can look on YouTube and see this being demonstrated by many people.
If you have any money left over, you might want to try some of TECC's fancier liquids while they're on sale. The
low resistance atomisers for the Tornado are also good (even more vapor) but you do have to be careful to keep them wet with juice (but not too wet) or they will burn out fast.
Don't be too frustrated. Most regular users started with an inferior model before discovering the 510-based models (Titan/eGo/Tornado/etc), and just learning how to use the things (inhaling, refilling) required a little time to learn by experience.