Now the problem with this is that it has a time limit, 20 minutes once activated IIRC so you gotta play fast nonstop as many match as possible within the given time. For this, playing 1-hole matches is clearly more advantageous but unfortunately there aren't enough players in higher levels (Montreal and up) so most of times you do nothing but waiting for an opponent just watching that stupid avatar pics sliding by over and over. Sorry but I'd rather play anyone in lower levels than just killing time for nothing.
30 as has been said.
also when you say Montreal and up. that leaves you with Montreal, tokyo, Manhattan, and Bellagio.
of those 4 only Tokyo is one hole matches.
I can go into a bunch of stats but suffice to say you are better off spinning in Tokyo and playing one less match than playing in Rio. Assuming you can maintain a decent winning %.
Tokyo drops more gold and platinum boxes than Rio.
and those are your two choices for one hole matches. Rio or Tokyo.
(chelsea also for newbies)