I use the MTH smoke units as a rule, though I keep a few LC+ smoke units around, they're a bit smaller and fit in places I can't put the MTH smoke unit. Most of the time I use the smoke unit on the left, occasionally in small stuff I use the one on the right.
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The Super-Chuffer II provides the chuffing smoke, smoke at idle, and also optionally controls and LED headlight for Rule-17 operation and automatic cab light operation.
The Chuff-Generator gives you programmable chuff rates and also optionally controls ground lights.
I stock the smoke units and supply the store with the other products.