If you want to get a carto tank get one from ibtanked, they are awesome.
BUT, the issue lies in cartos themselves. IMO almost all cartos out now have horrible QC issues. Its really hard to find ones that are good that fill and don't burn.
After starting with the 510 back in the day, going to VV/VW devices, carto's, carto-tanks, vivi novas, Protanks, I have recently switched to mech-mods with RDA's. I don't think I'll ever go back. (my Provari is collecting serious dust at the moment) It is work at first and requires a little electronic knowledge but the payoff is huge. Better vapor and cheaper.