The RX2/3 is extremely easy to disassemble/reassemble so, even though a lot of people reported issues with the 510 connector and the wiring, even though some people have typically been crying a Yangtze river on the internet about these issues, it is still a great mod if you know how to use a dremel and a soldering iron because then it takes literally minutes to fix these issues, and, now we are only assuming that you WILL run into these issues. I own the mod myself. ArcticFox is quite simply a must have. I use it on my RX300. The preheat in ArcticFox gives you the option to dial in your own custom power curves in VW mode. This alone is why similar priced mods pale in comparison. If you vape at reasonably high wattages and you don't mind the extra size and weight of the RX300. Then get the RX300 and four VTC5A batteries. Don't listen to other people talk about which battery is better─excepting only one person, who goes by the name of Mooch. Always make sure to use ONLY a separate battery charger for all of your Lithium rechargeable batteries.