So far I have heard good things about the Sigelei, the Smok, the Snow Wolf, and the IPV d3. I guess the "best" mod depends on personal preference, but which is the best for the price, which provides the most value?
That is the most important factor in your decision and reading on, I see you went to a B&M to actual see and hold mods.....great move! I have several mods with varying designs and all are my favorite depending on when I am using it. The only one I have that you mention is the D2 (which I assume is aesthetically the same as the D3). Not my number one, but great when I am out and about short term. Love the small size, yet every tank I have fits nicely on it.
Is getting a dual 18650 mod worth the additional investment in batteries? I feel like I'd need at least two more and a charger that charges more than one battery at a time. I'm trying to keep my investment under $75USD but if I could get a Cuboid kit that would be great, I was also looking at the Smok Xcube 160w, with the TFV4 for a dual 18650 mod.
If you are going to run the TFV4 or similar tanks, a dual battery mod is worth it. More up-front cost, but extended battery life is well worth it, especially of going out for the day. Even then, I don't trust my Sigelei 100+ (dual 18650) to last over 6 - 8 hours, but your results may vary. At least a 2 bay charger is a must, as are more batteries since pairs
must be married.
Having said all that, I just received my Sigelei 213 a few days ago, and although there are some complaints, it is sure to be my new favorite mod. Looks, size, weight, and battery life are great (some are saying battery life is equal to or greater then their triple 18650 mods, but I can't confirm that). Got mine for $80 and that included 2 batteries. It looks like they are coming out with an identical (although it may be slightly heavier) Fuchai 213 model for almost half the price that comes in more colors and (supposedly) corrections to "problems." Might be worth a look.
There are a plethora of options to pick from depending on
your vape style and back-ups are always good! Good luck.