When I first started vaping, we didn't have any 5v and we didn't have any LR attys or cartos. And yet, I started vaping and never looked back. It was that good. But then came the 5v devices and we all thought we were in heaven! Of course, back then, we had to be plugged in to the wall to get that 5v, but it was worth it. When they came out with LR attys, I thought it was very close to a 5v vape. Not quite the same, but close. It was so much better for me that I knew I would never go back to the regular attys. Now I own a lava tube and switch back and forth between it, my provape and my eGo. There is a difference in that the 5v vape is hotter and you do get more vapor, but I don't think it's so much more that I would call it "superior". Just my opinion. I use my lava tube or provape when I'm sitting at the computer or watching tv, but my eGo is better for carrying around in my pocket when I'm up and about and doing "stuff".
I wouldn't say that you "need" to go to 5v. If you're happy with what you have, that's great - that's more important than anything else. If you "want" to try the 5v and for a reasonable price, I'd suggest you try the lava tube.