The 2015 model floor plan was named 37MD...the 2016 similar floorplan is the 37RB.
Your letter specifically lists the finishes and the only options available on that model...that's good.
But, the bug screen was not available on the 2015 model.
If you do the e-mail batch, I expect 2 types of replies:
Dealers will reply to you in non-specific terms seeking to get you to call them to discuss the deal.
Or, other dealers will just ignore the e-mail as it does not give them room to wheel/deal.
It is an interesting idea that is available in the car buying world, but RV's? Probably won't work as desired...even MHSRV will make final concessions only after verbal communication (then you fly-in to close the deal).
Agreeing on a purchase price doesn't have to be in-person, because it is a new RV, but I expect at least a phone convo is needed to get the best price. That's how they work in price matching and also when they try to sell stuff like extended warranties or diamond shield
Be careful with these items