YEAH! M&StL is one of the four secondary railroads I collect/model. I bought my son the M&StL starter set a few years ago, my first purchase upon returning to the hobby.
Since then, I've been working to collect everything released for M&StL, and thanks in no small part to a number of folks on this forum, I've tracked down quite a bit. Got everything from Lionel, MTH (other than their ore car, I believe), KLine, and Williams... and I always have my eyes open for other things I may have missed.
Sadly, mine is boxed up at the moment, as you can see. My favorites are the K-Line diecast hopper, the MTH tank, and the Lionel PS-1 box. I'll pull them out for a quick photoshoot tomorrow.
I've upgraded all the PW and MPC to modern sprung trucks (as well as the AF boxcar), and I've added a pickup/light to several of the cabooses. Power is provided by the MPC GP9 set, the blue starter RS-1, and the F unit A/B combo from a couple of years ago. Will probably add a PW ABA setup at some point. LOVE this road and REALLY enjoying this thread!