So the general consensus on the early TSW rails seems to be that they were unsightly, fragile, and otherwise a literal bolted-on afterthought, but since I don't have access to the once-numerous CHP 4006s and I'm getting a 5906TSW soon, I'm just curious what lights actually work on them. Of current ones I'm only aware of the Streamlight TLRs having compatible rail keys but what else will work? Will the universal keys on Surefires X300s fit? What was commonly mounted on them when they were current issue?