Duffinator said:
If I receive ALL local OTA channels with the antenna mounted in my attic is it still better to have it mounted on my roof?
Of course you get a better signal the higher you mount an antenna and the less obstructions you have. It is misleading of anyone to insist that everyone will get a good signal in their attic just because you do.
In the Washington, DC area, the company I used to work for stopped doing attic installs because customers were consistently upset with the quality of broadcasts received with attic mounted antennas and roof mounting consistently produced better results. About 75% of attic installs were removed and relocated to the roof to improve reception.
That left 1 out of 4 people with attic mounted antennas happy. A 25% satisfaction rating puts most companies out of business and everyone looking at OTA antennas should be prepared for the concept that they may need to mount the antenna on their roof to get the reception they are hoping for.
So, yes, you will get better reception with a higher, less obstructed, roof mounted antenna. It may have absolutely no impact on your image though.