Personally I wouldn't bother with an rg6 these days.
I love my projector, and I don't think I could go back to a smaller screen. The biggest issues is 1080p is where the affordability stops. You can get a pseudo 4k(pixel shift) for around $3000, but true 4k is closer to $10 000. From what I've read though, the pixel shift do a really good job:
http://www.projectorcentral.com/4k-projectors.htm
I'm still using 720p becuase I am kinda(really) cheap, but I may upgrade to 1080p soonish.
It depends on your room though. I've got an ideal basement setup with no outside light.