I had answered this in a private message a while ago
so here is my thoughts.
They are both different machines
but both very good in their own ways.

Brute Force 650i (607 lbs)
-Very fast, quicker than the 800 Sportsman.
The 650i actually has a more powerful, harder hitting
engine than the 750i. This is due to higher compression,
straighter intake tracts and higher performance cams vs the 750i.
-Firm tight ride , not hard. Great control.
-Agile, , tight turning.
-Great milage. Went 100kms trail ride, 7 hours and still
had a 1/4 tank left. Apparently the 750i uses much more gas.
-Excellent shifter **** and gear box set-up.
-The Engine braking feature in 4x4 is excellent.
-Will be upgrading the tires to ITP Mudlite XTR's.

Sportsman 800 Stealth Black
-Only a couple of weeks old so not much time with it.
-Coolness factor with the Limited Edition Stealth Black finish.
Great looking machine with chrome wheels and large 26" tires.
-EFI sounds excellent with dual exhaust.
-Much softer ride than the 650i, not as firm and might be
a little loose in comparison.
-I had only taken the Polaris out once and drove in about 4-6 inch mud, so
it is really hard to compare a trail ride performance comparison. However the
800 went through this mud with ease and you could really feel the power and torque
that is available in the 760cc motor.
-The deluxe stock tires and rims do not need replacing. I think they will
be sufficient.
-The speedomoter set-up is complicated and not as usefull as the 650i's
total digital unit.

Overall, both machines are great in their own way.
The 650i is for up north trail riding while the Porais 800
will be kept for most part in the city and used in the winter to drive through
snow and plow snow as well once I get a blade.

Hope this helps.
It basically depends on your needs or uses.
You would be pleased with both. The Stealth though,
is the nicest ATV I have seen..Very nice!!

 

You can't blame the others for not responding. If they were to respond and lets say the competition is Ride, weight, and cost then they can't win! If they complain then they are sore losers.