Two different planes Phil
Phil: They are both great but two different to really compare, at least in my opinion.
One uses an expensive 4-cyl and the other uses a larger very much more expensive 6-cyl. One burns lots of gas, the other burns a lot more gas than, lots of gas. (I know you can lean your 540 and throttle back, but cruise at same speed, a 540 is thirsty.)
Do you need to haul 4 seats around all the time? If the answer is yes than the RV-10 is for you.
There is no way around two v four seats. My feeling is if I want to fly 3 or 5 people around I will rent a C-182 or Seneca II.
Aerobatics? Forget it with one of them, buy a RV-7.
Cost? I am 100% sure a RV-10 will a significant amount more green. Check the tax situation on airplanes in your state. If the "mill rate" you pay is on value or cost of the plane, it will be the gift that keeps taking.
The answer is in your head and what kind of pilot you are and what kind of flying you want to do. The planes are totally different. Usually its a slider or tip up canopy debate or taildragger or trike. Some times folks debate RV-8 v RV-7, but the RV seven v. ten is a unique problem.
I always wanted a 10,000 sq-foot hanger with a Citation, Pitts, Super Cub on gear and floats and a RV or two of course. That is not going to happen, so one RV-7 is everything to me, which it is, just not the floats or 6 seats. I understand the desire to have one plane do it all, but aviation being what it is, there is not everything plane. There are trade offs and you will have to make that decision.
Frankly I fly solo most of the time, dual a 1/4th of the time and about once or twice a year I wish I had a 4 seater to fly. If you are a family man than the RV-10 may be the way to go. Like I said, consider flying the two seat RV-7 for fun and dual X-C, than rent the C-182 for that occasional sightseeing flight or cross country to see the kid graduate college with that Art History Degree.
(no offense to those who majored in art history.)
The "sport plane" mission or "total performance" as Van's coined was fast X-C travel, short fields, Acro and fantastic handing. The RV-10 is still total performance buy biased more to the X-C and clearly not Acro. The solution may be a 4 seat RV-6 (recent thread on VAF).
You want to choose between a Porsche 911 and nice Mercedes. Both very nice. One I want to take out on a weekend trip with some curvy back roads. The other I want to take on a long trip to Florida and Disney World with the "kids" or exotic dancer friends, as the case may be.
Before the flaming starts, the RV-10 is sporty and fast, but it is not going to handle as well as the RV-7 or be as fast. (I know the, "why can't you do acro in a RV-10", thread is coming soon.)
The RV-7 will do it ALL on less gas (except all two more butts). On the other hand the RV-7 is still great for X-C traveling for two and reasonable bags. (It's fun teaching some woman, not all, they can go for a week on one small bag.
) I traveled all over in my old RV-4 with the girlfriend, including camping gear!
P.S.: Take off landing distance? If you are into short mountain grass strips, a super light RV-7 with a big engine will be better than the dash ten.