I think for a single week's trip, you won't want to do anything or certainly spend any amount of time or money making any 'changes'...just use the coach as it is designed and see how it works for you...you may find that the normal vehicle air conditioner will be just fine, or you may find that trying the roof a/c with the generator to see how it works will be a nice trial, in case you need to do that after you 'buy' one....
we travel a lot, and hardly ever run the generator just for the a/c unit, and our coach is 35' with two roof airs.... it might get warm in the living areas behind the driver and passenger, but that's just part of traveling in the heat of hot summers with lots of humidity... you can certainly also easily plug in floor or table top fans if you have an inverter in your RV, which adds a lot to the 'coolness' of the RV while traveling.
Don't sweat it! A lot of people may 'say' things that might scare you, but getting out there and finding out yourself is the best course - some folks like it really 'cold', while others are very content with 'cool', while some of us others just open the windows and let mother nature do her job! : )
'14 Palazzo 33.3 bunkhouse 34' diesel
KingTailgater2 Dish HD, 100w/5a SOLAR, BlueOx
100,000+mi since '14 - US, Alaska, Canada - Hiawassee, GA! (also, '14 Gulfstream Amerilite and '07 ForestRiver Rockwood) : )