Welcome
xvii!
IOWN is right - there's a lot to choose from out there, and everyone's tastes are different. One person's neato feature - like even something as simple as the shape - is another person's annoying feature, lol.
Personally, we started vaping with automatic 510's. Eventually moved onto a Mega eGo. Now we have a top-of-the-line ProVari with variable voltage. When it finally came time to try 5v vaping...it was frankly too hot for my liking, like in a way that made it difficult to even enjoy or taste the flavour.
But it's really a very subjective thing - a lot of people
do love 5v vaping. It's just not for everyone. So if the choice is strictly between 3.7v and 5v...I'd advise going with 3.7v for now.
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Voltage aside...if you're on a tight budget, I'd recommend considering an
eGo (650 mAh) or
Mega eGo (900 mAh) as your next step up.
(In case you don't like pink, lol...no worries, they come in many colours.)
They're very affordable at a mere $25 to $30, & you'll see the difference in much longer battery life right away. The output voltage to your atty or carto from an eGo is going to be around 3.3v...definitely not 3.7v. But that's still higher than what you were getting from the 510. She'll see you through while you contemplate mods
(there are a lot to contemplate).
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If you already have more money, like for investing in a great mod...well again, you're going to find a wide variety of choices. Which is fine. But if I could only recommend one, and it strictly had to be a 3.7v device...I'd personally go with the
ProVape-1. Here's a size-comparison photo next to a lighter - very compact, as you can see:
The shape is neato, with those neat little groovy ridges; it's very professionally built, & it has some of the same safety features that the ProVari does. Features that a lot of other 3.7v devices for a similar price don't have. And it's $60 less than the ProVari. Though as you'll see in a moment...I think that extra money is well worth the investment!
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Now while I wouldn't
ordinarily recommend the following to someone who has only used the 510 to date - if you think you're ready for the plunge, this is the mod amongst mods that I would recommend to anyone. The variable-voltage
ProVari:
the ultimate PV, hands down.
The numerous features are just awesome. Safety features that prevent
(amongst other things) a short-circuited atty from harming your PV; built-in multimeter capability
(so with a few button presses you can check the resistance of your atty or carto, or the remaining battery life). It's easy as hell to use
(just pop the battery in, press the button a few times to access the menus on the lovely LED screen...& a few more button presses to change any settings you wish to change). Has a standard 510 connection. It's surprisingly compact
(photos & vids make it look larger than it is, somehow) - fits nicely in your hand, easy to take out with you. It's built with
extremely professional quality, no exaggeration...more than we had imagined. It also regulates the power, so that
every drag you take is as fresh & powerful as the first one - from when the battery is freshly charged, right down to when it's drained. No more dwindling power!
My feeling is that a lot of the 3.7v mods out there just aren't as impressive as they once were - in performance
or price - now that the ProVari is here. That's not to say other devices are bad - some are simply different
(like a hand-crafted, beautifully polished wooden box mod); but some are definitely due for a reduction in price. Then again, the ProVari might not be everyone's cup of tea...perhaps some people think it's ugly.
But we love ours! If you like, you can check out this great video review from Scott Bonner in the UK, to see her in action:
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Oh and to answer your other question re: ordering mods from the States...I can only speak from personal experience re:
ProVape. Would rather not go into detail here...but rest assured, you won't have
any problem getting a mod through from them. I would strongly advise going with the fastest shipping though, rather than the cheaper option - when your order is sent out, it'll make the difference between a few days wait, and a few weeks.
IOWN is right though...usually, so long you don't order anything with nicotine in the same order as your mod, things
should be fine.
(It probably wouldn't hurt to send an email first though, just to make sure the folks you're buying your new mod from will mark it discreetly on the shipping label.) It's mostly large overseas orders of cartomizers, & a few atty orders, that have been getting some grief from Customs of late.
Anyway...yeah. Good luck in choosing, happy vaping, and welcome once more!