Det, In the cenotes I seen problems going on, theres alot of dive operations there.
Bring spare O-rings for tanks that seemed a issue always, of course they get used alot,
the guide or shop would have a hard time to make sure every O-ring is good.
After looking at the old gear I stopped in the dive shops to look at gear, alot of shops have faded BCD's and scracted regs,alot of use.
you never Know what some shops Have, To not bring gear is a plus, I kept a bag in the back every day ,the masks were there, they were nice, to rent everything is only $15.
when we talked to locals, They ask what we like doing, We said we are here diving
with divemex, They told us how well they take care of your needs.
In the morning the other shops want you there earlier, having coffee at starbucks we watched divers running to the other shops, we finish go back to hotel have breakfast, then go to shop for diving. Much more of a relaxing dive vacation.
Hope this helps or clear a few things up for you.