I read your question and thought I would answer you with my opinion.
The thing you need to decide is what do you want this for? Trailing riding or working and how much of each because they are both better at different things.
I own a FXT Pro LE and a Honda Pioneer 500 –for me this is the ultimate combination, one tight trail machine and one work horse that can be trail ridden. I looked very closely at the Pioneer 700-4 and one of my close friends own one. It is a NICE machine and is a good do it all machine. It can haul 4 people, can work and can play. Does it do them all the best, nope. The Mule will easily out tow it (rated at 2000lbs, Honda at 1500), and haul more people with out breaking a sweat. (and weight in reality) The Mule has a very well proven 3 cyl. Car motor in it that has a very smooth power to it. The Honda is faster off the line and overall. The Mule is NOT a fast machine, will do 40ish but you can feel the motor is all torque, not that snappy HP that some people like. It is a belt driven machine but that system is extremely well proven and not really something to ever worry about. The Honda of course has the “auto” style transmission and you have gears that shift. Again a solid system with no major issues at all. The Honda does not have a front locker, that is one thing I wish it had, but in reality mostly not needed for what the Mule normally does. The Mule hauls 4 people BIG people with extreme ease, 6 normal adults fit fine and in a pinch you can cram a ton of kids in it if it is ride across the farm field. I have a family of 4 and often the kids each have a friend over so being able to carry 6 is a big perk for me.
The bed space on the Mule is WAY bigger than the Honda both in two (or3) person mode, and even with 6 adults on board the Mule still has some bed space unlike the Honda. The Mule is longer by about 19” and wider by 4” (Honda 114 long and 60 wide) , Mule (133 long and 64 wide). The Mule has a 16’ turn radius and the Honda about 14.8’ so fairly close there. The Mule does offer power steering however, the Honda does not. The Mule looks a lot bigger, it really is not that much bigger but looking at it – it seems huge….
Ground clearance on the Honda is 10.5” and the Mule is 10.2, again close but the Honda is also shorter so that helps it some. When you look at the underside construction the Mule is much heavier built, that is easily noted when you look at the machines weights (Honda 1396, the Mule 1898) The Mule will easily turn a larger tire if you have the urge (I run Pitbull 26’S – They run big, and I can feel no difference in power).
The pioneer has a front locker as I mentioned which is nice, the Mule has a rear unlocker which is also kind of cool. Basically you can make it one wheel drive so you can go in your yard and no tear up the grass making a turn. I personally feel both these machines should have both of these features.
The Mule has about 8.5” of wheel travel on all 4, the Honda has less up front but a bit more on the back so it is sort of a wash. As for ride, I find they both ride well and are more than acceptable. As for noise - I will say the Mule is very quiet, I can talk to both the front and rear seat passengers without any problems. I have a roof and windshield on mine and a lot of people claim that makes it worse but it is still quiet. My 500 is a good deal louder than the larger Mule. I cant recall paying much attention to the Pioneer 700 so I really cant comment.
Factory lighting on the Mule is a bit better from the factory if you get the LE – it comes with reg. lights and built in LED driving lights. It also has a much more powerful electrical system (it is a car motor so you have a alternator as well as a full size battery on board). The Mule is also premolded for installing switches in the dash for extra lights and such. A power dump bed option is also offered
The rear bed has a built in “headache rack” , steel diamond plate flooring, flat tailgate system, and a standard 2’ receiver hitch. 2” accessory rails run the length of the bed and with the mounts allow all kind of quick detach stuff (gun cases, boxes, etc)
Fuel capacity is very close – both give you appox 8 gallons with will get you a good ways without refueling.
The Honda does have some storage space but the underside of the front seat on the Mule can be set up for a lot storage (Proarmor makes a locking box and others have stuff out) – you also have a few cup holders and a glove box as well as a few spots on the dash for storing stuff.
The Honda is a better price (MSRP $11,700). Mules run from $12,999- $15,600) You seem to be able to deal a lot more on the Mules than the Honda right now and the higher price Mules does have a bunch of extra stuff (Power steering, a roof, alum rims, etc) so depending on what you want the prices gets a lot closer together than it first seems.
Warranty – Honda gives you one year cover, Mule gives you 3 years coverage.
The Honda is clearly the better machine if all you are going to mainly do is trail ride and maybe haul some bags of mulch around from time to time. If you are like me hauling LARGE loads of firewood, 2-3 deer along with 3 hunter at a time, get the Mule. It is still fun on the trail but it larger and it is NOT a hardcore 4 wheeler.
Hope that helps…