I am 54, weigh 238 and 6 ft 1 and get in and out of my M just fine. I can see where the additional 30 lbs might be a hinderance if your not in good shape so thats a good a reason as any. As for the gas milage, your right. Duh!
You got lucky at that price, like the guy down the street rants, "Don't forget to leave and drive it like you stole it" which you pretty much did.
Congratulations.