The majority of my collection is LTI and MPC era products. They're mostly bullet proof and can be found at great prices.
Though I tend to stay away from the items with plastic trucks, there are plenty of durable items with those trucks like the ore cars. The majority of rolling stock I try to get have die cast trucks and couplers. If they don't, they'e usually easy to replace with those trucks. They give the cars some better weight and the couplers usually hold better.
Locomotive wise, much of the small can motored engines like the RS-3's can't pull much, but they can run basically for hours on end. The AC motored engines can't, but they usually all still run well and usually pull better in the larger locomotives like the Hudsons. Other locomotives like the Southern Mikado and ALCO PA's from 1992 which have big, heavy duty can motors can pull significantly well - just as good as any current day locomotive.
