The 200 polaris (phoenix??) is an Aeon machine and IMO something that's not the most dependable. If not the Phoenix, I could be wrong..
I look at the "fun rating". LOL
A modded mini may be more fun at 9 then a bigger machine. This has been my expierience anyways.
My kids didn't get on the bigger machine till approx 12. They had fun (fast) mini's tho.
I guess I'd let the height/reach thing guide me most if expierience isn't a factor.
The modded LT80's can go well in sand. I have alot of motors going up olds.
If he is able to go bigger, dare I recommend a 300 mongoose (KYMCO). It's a 300 4 stroke with a CVT (belt) drive. No shifting except from park to forward or reverse. It's a tame machine (my wife loves mine).
I have the 250 mongoose that I rode in 2- 12 hour races. I can attest to the durability of these machines. They have Honda roots. Even the wheels and other things will swap with a Honda. I have a TRX 450R axel in my Kymco. LOL
Good luck with your decision. I commend you on educating yourself first.
P.S. If you look at the modded LT80, PM me with what's been done, what pipe, etc.. I'll try to advise you on what the machine is capable of and what to look for.
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88 framed 2-fiddy-R 300cc's
2000 GNC 40+ class 5N
2001 GNC 40+ class 9N
2004 GNC 40+ class 9N
A few fast LT-80's
Father of the "11" time National Champion and worlds fastest woman ATV racer.
Survivor of the 12 hours of ATV America '04 and '05!!
TT RULES!!