A22 very similar to the VLX (06+ years). that is the main reason we bought ours. My 2 favorite wakes of all time are the VLX and Xstar. I spent some time behind a buddies 06 vlx, 3500lbs or more and no wedge. Loved it.
When Axis came out and after talking with matt and adam about the hull and how close it is to the v25 (malibu vlx) hull, I was sold before even seeing or driving one. Then my wife and I drove it and it handled incredibly, just like the vlx. we were sold.
IF you like the VLX wake, then you will like either the A22 or A20.
1. dont pay much attention to gas, and have no time on an A20. We ride with 3 or 4 riders, 4000 lbs, no wedge, core prop on a 335 motor. We take 2 sets each and I burn approx 15 gallons. I can do this almost 4 days without running out of fuel if I wanted, but I always run with the fuel tank full = more weight
2. I do think 2 feet will be HUGE with up to 8 people. With 5 adults and 2 two-year olds, the A22 starts getting tight, especially with people moving around, getting drinks, changing riders, ropes, boards... I do not know where the extra 2 feet come from, I assume in the cabin area as the bow looks the same.
3. My opinion. Price out the A20 loaded exactly how you want it, then order the A22, stripping it down to the same price as the A20. Then add all the extras yourself during the next few winters. I think if you get the A20, you will miss the extra 2 feet and may regret it. If you get the A22 you will miss the heater, or shower, or LED's... but you can add these later, for cheaper. And since you said you plan on keeping it for the long haul, adding options yourself later will force you to become an expert on your boat which will help you for years to come
either way, you will love the boat. Have fun with the new boat buying experience, we did!