I played there on my last trip. It's a pretty cool experience. Once they see that you're a foreigner they will be all over you trying to make a game. I think I bet 500 pesos ($10) for a race to 3 in 10-ball. Plus you have to pay the racker 50 pesos ($1). But there was no table time fee in my experience so I guess that's what the racker fee covers.
As soon as I walked in they got all excited, gave me a cue, and chose an opponent for me. It was like the whole room was involved in our game. Even the guys on the side would be betting for or against me and would cheer me on. Then they switched opponents on me a few times to make it more fair depending on the result.
I will say however, don't go into the room expecting to leave with any money. Not because they are necessarily going to be better than you. They will find you a fairly even match but the atmosphere there is very different so it's hard to get comfortable. These guys are also living in that room 24/7 gambling all day to survive so they are very comfortable. But this is their job so if they don't win, they don't eat. Plus the bet is a lot to them and they are usually being backed. So there's much more pressure on them to perform. But they are all working together (the ref, the room owner, the backer, etc.) to win your money. If the match is close they will probably cheat you on a few close calls and end up winning. That's just the way it goes. Just consider the bet a donation and chalk it up to a good experience. Trust me, they will find a way to win. Maybe not the first few sets but they will eventually get you.
Also, I was in a very remote area so it wasn't easy to find a pool hall. Outside of the poolhall, pretty much everyone I met didn't play pool. They were much more into basketball, which is odd because the average height is 5'-1" lol. So pool is not as popular there as it may seem. At least where I visited. I'm sure the experience in the big cities are going to be much different too. Good luck!