Scrapiron,
For the same reason I have moved back to Lionel smoke fluid for Lionel steam and diesels. I have replaced the smoke unit and fans on all my units. I could not understand Why. Mike R and the Lionel crew told me their fluid is designed for their products, doesn't leave a film on the components or as you saus gunked up the works. Send lots of money on alternate fluids and quite frankly got tired of makeing repairs. I gotta belive their is some truth to this as my G Scale LGB units do not work well with alternatives so I will rebuilt that smoke unit and go back to LGB. Might be one of those psycho issues but.........
However, on MTH, I don't seem to have that issue, but with that said, I will use all the remaining alternate fluids I have and then probably convert to MTH fluid for MTH products.
The fact that Lionel has been making other scented fluids helped me move in that direction.
I like the other manufacturers as well but given the new comments in the Lionel Niagara Owners manual, they must have the data to support their policy.
Oh, well, I still have about 20 bottles to use up in my MTH engines that I got at York and since theysmoke fantastic, I am not gonna worry to much
