How much weight are you towing? Does yer trailer have electric brakes? If so, are they set correctly? What are yer driving habits like? I hope you don't do any abrupt braking or ride yer brakes down a lot of hills...
How good are yer brake lines and other brake components? What was the color of yer brake fluid when you bled out yer brakes?
I personally would stay away from the slotted/drilled rotors...
I picked up an extra set of rotors off of eBay fer cheap...haven't put them on yet.
I wonder if anyone ever made an active brake cooling system running off of an electric blower that you could direct with some hose?