SAM is pretty good for not messing up skills too much when lag is an issue.
DRG i haven't really played since ARR/HW so kinda out of the loop on their skills but from the little i've played in POTD it's not exactly my cup of tea.
Ninja is fast and light and fun as hell but prone to using hand sign failure a lot, due to the latency involved with hitting skills
MNK is super heavy on rotation and positional aka need to be to the side or behind, but it's not too bad but not great for solo either, since they need to be behind or to the side, of course if you can get someone to hold the aggro or a tank choco then it's probably a bit more acceptable.

Out of the 4 I suggest SAM or DRG it's the least likely to fail and easiest of the 4 to use.