The Wismec RX200 is a very good choice. I have two of them and recommend them highly. There are two known problems with it. One, the balanced charging board doesn't work well for in-mod charging. I strongly recommend a stand alone charger. Next, the 510 connector in the mod is not as good of quality as it might be. It can be lived with, or replaced, but I do want you to hear the caveat. The
batteries I recommend for the RX200 are the LG HG2s-- those are the ones I use, and I have a dozen of them-- or the Panasonic 30Qs. Batteries in removable battery mods should be "married," that is kept in pairs, or triples for the RX, and always used and charged together as a group. Don't mix and match, is what I am saying. I'll be happy to tell you why if you're interested.
For further advice, think Nitecore or Xtar when you buy a charger. With the RX, you'll be charging 3 at a time, so a 4-bay charger is a wise choice. I have a Nitecore D4 and and I4, as well as an Xtar VC4, and can recommend any of them as solid and effective products. I like the Nitecores slightly better than the Xtar. The chargers can be safely bought on eBay from top rated sellers, but buy your batteries only from known quality suppliers. You're going to want at least 2 complete sets of batteries, that is 6 total. The easiest way I know of to keep your batteries married in pairs is to rewrap them in colors; Fat Daddy Vapes is where I bought the wraps you see in the attached photo. Finally, if you are a bit turned off by the janky 510 in the RX, I personally think the best buy in a two battery mod right now is the
smok Koopor Plus. My RX batteries (the yellow set is in one of the mods):
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