hi nthere
your choices are endless,
the most popular ones are
smok tfv4 but only use that in the sug 150 its a poowerful tank
after that
maganus ni/starre pro - same tank different name
it needs power as well so the sig 150 is great fo rit
the istick 50 si barely gonna run it at its best
next up
uwell crown
- hmm same issues as the starre/maganus it needs over 50 watts to shine on its stock coils
the best tank for the 40 and 50 IMHO would be the subtank plus with ni200 coils
or if your into building your own coils - get a billow v2 and depending on your build any of your mods could run it
and one otther that should be fine on any of those mods is the atlantis