That's awesome, congratulations. Dang I didn't know 4s went 170ktas on that little gas, the -6As I'm looking at are closer to 150KTAS on that gas (lot of people fib about speeds, but some RV owners have been candid with me about real world cruise numbers).
Funny you ended up going the RV route while looking at 4-seaters, that's exactly what I've decided to do after 9 years of owning certified. I did it the other way around and let me tell you, though it worked out for my financials and family makeup at that time, I don't think you'll enjoy the shift to certified rules after having owned an EAB. Lord knows I wouldn't. I'm burnt the hell out of the mother may I stuff, the pricing structures, and the ever present recurring ADs, or the threat of them. Primary Non-Commercial getting snuffed back in 2015 really soured the hobby for me; tbh I don't think I ever got over it. I think you'll regret selling the RV for a certified plane.
Had a come to Jesus with the wife the other night, and she agrees. I need to go EAB or quit, there's no point in spending all this money if I'm not having fun anymore. Leave it to my wife to be the one to push for a 2-airplane solution! So RV-6A is where I got my eyes set on; I'll cross the 2-airplane cost bridge when it hits me in the face.
Blessings and a happy 2020 to you and yours!