Rainy season? Actually almost a carbon copy of Miami, at least on the ground. Starts dumping rain HARD every afternoon, anywhere from 30 minutes to 2 hours. Usually starts at 2-230 in the afternoon, as opposed to amost exactly 330, at least in FT Lauderdale. Rainy season doesn't mean it rains all day. it does rain every afternoon for a bit.
Flying? Yeah you are dodging T=storms every afternoon and evening. You get used to it.
Difficult training and its' effectiveness? Can't answer that one. The proficiency of the local FO's was all over the map. The expat FO's on the 320 pretty much said the local Capt's were mostly pretty good to fly with. I guess I would suggest that makes their "difficult training" somewhat successful.
It ain't Delta or BA for standardization or standards, but there are a lot worse places to fly. I liked flying here far better than my last job.