Have never seen the 4Points rooms, but the Sheraton on Sherbrooke is quite a nice property, especially if you get a Club Level Room.
That being said, the room I was in felt very crowded, and nothing exceptional. You should probably see what the price difference is between the two, and decide whether the possibility of a Club Level Room is worth whatever the difference is.
But I will say that the Omni is very nice.
[Edited for spelling.]
[This message has been edited by SMessier (edited 06-13-2001).]