Chuck (I hope that is your name), that unit is huge, and the big boy is even larger?
Could you give the dimensions or shoot it with a ruler? Also, what's on the bottom of the left hand tank? It sort of looks like mounting hardware, but cannot tell.
Just guessing, but it sure looks like the MTH has a much larger fluid capacity.
It seems that the right hand part of the MTH is the element and the fan, is the left side the reservoir?
On the question of syncing with the chuff, the MTH fan leads are separate, but just turning the fan on and off with the chuff is probably not good enough.
Several manufacturers use electronics to not only spin the fan up fast, but to stop it quickly, much more quickly than just turning off the power. That helps immensely with making distinctive "puffs".
My understanding is that TAS does this, and I know MTH has a patent on this and assume it's in their controller electronics. If you use the MTH unit by itself, I suspect you do not get this benefit.
So, for installation on locos without the MTH DCS controller, I would expect synchronized puffing would not be great.
Anyone experimented with this?
Regards, Greg