I'd say it's fine if it's a hamster proof room and you're there all the time to keep an eye on things (they have been known to climb curtains!).
Our syrian now free roams in the living room. I've blocked off a couple of areas I don't want him to go, but he does sneak under the door sometimes, so would suggest putting a door draught thing there to block any gaps (we stuff a dressing gown in front of the door
).