$110 for the module, then $100 for the receiver, and you are stuck with a 7 channel radio with no trainer port. Also you would be stuck buying Spektrum receivers for the module.

I have an older 7UAF radio and I was thinking on the add on module last year. Futaba has the 7 channel setup for about $250, and the 8 channel for a little more. For about $50 more you can get a brand new radio with a set of servo's and receiver battery pack.

There are no savings on add ons.

You just missed a good sale about 2 months ago from Tower Hobbies where they had the 7C radio with digital servo's on sale for $300. Then they had an email coupon for $50 off of your 300 dollar order making the price of the radio $250.00.