Neteller is still one of the largest payment processors for online gambling but lost a lot of market after they had to get out of the US market. Support works fine but can feel a little slow sometimes if you email them, if you contact the through the live support you usually get to speak to a operator within 5 minutes
Transferring money to poker sites is very easy and goes very smooth, seconds after you requested a deposit from the poker site the money is in your account and you are ready to play.
Neteller is supported by all serious poker rooms. Withdrawing and depositing money on poker sites is usually free as the poker sites take the fees on themselves.This makes it very easy to transfer money between rooms if you are doing bonuses.
Withdrawals to Neteller from a poker room all depend on the poker site how fast they process them, usually 2-3 days.