I am on my second Trails West Rpm, the first being there first year of them. There are a ton of updates between the two models, and the new ones are real nice.
That being said, Logan Coach makes some of the nicest Horse Trailer living Quarters (not taking anything away for Trails West), and have been in the game building high quality gooseneck trailers a long time. If you can afford the added cost of there New Snowmobile trailer, I am certain you wont be disappointed.
Charmac has also been in the game building enclosed trailers a long time. Some good, some not so good. But what they are offering now seem to be well done.
It come down to the Charmac and Trails West for me. I went with the Trails West because of availability, cost, past experience and the dealer.
As for the in floor heat, I have no idea if its needed as this is the first trailer I have had it on. We were able to get the sleds melted off before this so I doubt its completely necessary, but hopefully it aids in drying them off in a faster time saving some propane. We will see.
All three are nice trailers and will suit you well, good luck!