Intertops - Medium difficulty to withdraw especially if you play
freerolls. They have some ridiculous rules that make it a bit hard with freeroll winnings but it is possible to withdraw. I don't play there and I would not recommend anyone to play there (but this is just my opinion).
Betonline & Sportsbetting Poker - Very easy to withdraw. You get your money in 2-3 days most times. Sometimes a bit earlier.
For any Poker Room it is best to read their rules (easy to find just google them) and make sure you understand them especially the payout rules. If you unsure of something all rooms have some sort of support via live chat or email. It is always best to know what you are getting into and ask any questions up front before putting your hard earned money on a Poker Room.
If you need clarification on anything about Betonline & Sportsbetting Poker rules you can ask here I will answer them if I can. I play there often. For Intertops I do no know.