So what's your take on them? No real specific questions that I can think to ask.. how does the 1000 handle hard riding compared to the 500? I would think the wolverine would be the best trail bike but why did you make the switch?
Wolverine rides very smooth - comparable to my RZR. Wolverine will climb very well and finds a way to keep the tires planted due to the free working suspension. I installed the SuperATV lift and disconnected my sway bar resulting in a great ride/climbing unit. It went places in 2WD my Pioneer 500 required 4WD. No comparison between those two in terms of climbing ability primarily due to the limited articulation and lack of front locker on the 500. There were things I did not like about the Wolverine, but most were just nit-picking.
The Pioneer 1000 is also a great unit if you know, understand, and respect the DCT. The Pioneer 1000 hands down has more power, and it is noticeable. There were a few times when climbing rocks in the Wolverine when I had it in 4WD lock and was in a bind the 708 could not spin the tires unless you hammered it. I would say the Wolverine has more finesse. The Pioneer 1000 more utility. In terms of trail riding they are not too far off if you can get past the Wolverine looking more sporty and the Pioneer 1000 looking more utility. Spec-wise, both have about the same suspension travel and both bottom out the front when ridden hard. As smooth as the 1000 rides, the Wolverine rides smoother. Both climb well. I was actually surprised I was able to jump the 1000 without going nose down.
I made the switch from the 500 to the Wolverine for the ride, room, speed, and the climbing ability. The 500 is not made for speed nor rock climbing - although it can be done. It takes a little more "pucker factor" to take the travel limited, narrow 500 up difficult rock climbs. If you think about the nature of a low speed rock crawler as well as high speed rides there are a lot of similarities - you want width for stability, travel (articulation), and maximum GC at the lowest possible COG. Most people sacrifice some GC to gain some COG. IMO the 500 strikes out on all three. There were many trails the Wolverine and 1000 would walk right up that had the 500 almost flipping and spinning. If you ride like I do, you miss the front locker badly in the 500. The 500 has its pluses, is bomb proof, and is overall a blast to drive. However, (referencing speed) it would eat dust all day trying to keep up with a Wolverine or 1000 and would leave your teeth rattled. There is only so much 6" of travel can take doing 35-40 mph. If you want to ride "hard," whether rock climbing or going fast, I would consider a change. If you are just tooling around and trail riding, the 500 is a good fit. However, it sounds like you want more than the 500 can give.
I went from the Wolverine to the 1000 due to wanting more room for my wife and three kids. The Pioneer and Teryx4 were my only choices as I already have a Ranger CREW that stays parked at the farm due to it being too long to do anything but dove hunt with. I don't mud bog, so finesse and maneuverability are paramount.
They all have their niches, but overall the 500 is not built for speed nor comfort at speed. I will defend its reliability, fun-factor, and utility purpose all day, but no one who truly rides at speed or has ridden with RZRs or Wolverines can say the 500 would stand a remote chance of keeping up - and I only make this point as your question was about how do they do being ridden "hard," not how fun they are as the 500 is very fun to drive as I am sure you would agree.
If you want to carry more than one person, I think your decision has been made. I also looked at that rear seat when I had my Wolverine, but the life of my wife and kids mattered more. No way they would be properly protected in a roll over - especially at speed. If you are buying it with the intent of adding that seat, IMO don't. Go ahead and afford a factory 4 or 5-seater that is built with a certified ROPS for all your valuable passengers. Not to mention - give them some legroom. That add on seat is a crunch in the Wolverine bed.
On a side note, I don't believe the 700-4 would give you a great deal more of an ability to ride any "harder" than the 500 does now besides being able to carry more people. If you are gonna make the jump, go ahead and eat your loss one time and get something built to be ridden "hard." I truly do not believe the 700 with 4 passengers would outrun the Pioneer 500 by that much, and it is well documented after you get the 700 you will need to upgrade the suspension if you like to push your ride.
Apologize if I bounced around, I'm at work and am currently multitasking...