I am also in the process of installing whole house audio and a 7.1 + 5.1 surround systems, all ceiling installed and planning on using Monoprice speakers for at least the whole house system, and probably for the surround systems as well.
My house is currently gutted and I am running audio wire now. I have the whole house setup for 6.5" 3-way speakers due to small room size and limited places to locate speakers. There will be two 3-way 6.5" speakers in the main living area, one dead center in the kitchen and one that pretty much splits the entire room located at one end.
I am also planning on using 6.5" for the 7.1 and 5.1, with a 6.5" 3-way for the center channel. Once again, due to limited space I will probably pair the L/R speakers for the 7.1 & 5.1 with the Monoprice 10" and 8" passive in-ceiling subs respectively.
Does anyone see any drawbacks to this setup? I custom made plywood rough-in brackets that will accommodate up to 6.5", so if 8" speakers would be better for whole house, or at least for the bigger room, then I need to recut the rough-in brackets to size. I'm not looking for mind blowing sound from the whole house audio, but it should be enough to give good sound, and in the two smaller bed rooms, serve as audio for multiple purposes (i.e. computer, tv, etc..).
Also, would the Monoprice in-ceiling speakers be acceptable for use outdoors in a soffit and in bathrooms?
Pics attached are of the main living area, primarily of the 7.1 section of it. They are a little out of date, but it shows speaker placements and general room size.