I started out with a trigger I/O but quickly switched to a used Roland TD8 Brain & accumulated a bunch of mesh headed drums & rubber cymbals, which I still have a decade later.
The Trigger I/O was really unpredictable, as are most of the other trigger converters that I have seen/used.
Not sure how determined you are to use triggers predominantly, but if I were you, I would start building a proper e-kit. Much less hassle. Also, I am a beta tester for ToonTrack & also owned Steven Slate Drums and Addictive Drums. They all worked really easily with reaper via the TD8.
EDIT: Just looked up that Roland TM6 and was stunned by the price! I would sell you my entire TD8 kit with the TD12 drums, cymbals etc and a top quality Gibraltar stand for far less than that!