Anyone considering an EXC may first want to evaluate their riding skills. KTM's are street legal race bikes with race-oriented geometries, which are sometimes not the best choice for people with limited off-road experience. And while the 500 will lay waste to the AT in the woods, it also has relatively "twitchy" characteristics on the street.
The OP may have extensive dirt experience, which is a definite plus. If not, it may pay dividends to find a loaner KTM/dual sport and spend a day riding in various conditions. With its ability to deliver explosive power instantaneously, the 500 demands a rider's full attention. In the hands of the right person (aka KirbyKajin), it's magic. A novice may walk away with a different opinion.
A lot of truth here. When I got my 530 EXC, I was not what I would call an experienced dirt rider. I started on an 1150 GS, then went to a KLR, then got my EXC. However, I think my riding skills progressed the fastest once I got the EXC because it just handles so well and inspires confidence. With the GS and KLR, I was always fighting the bike's limitations, wearing myself out in the process, and developing "coping" skills that weren't necessarily good dirt riding skills. I've had to unlearn a few of those since getting the EXC.
The power difference is huge. So I have to be much more aware of what I am doing with the throttle, what my traction situation might be, and where I am pointing before I get on the gas. That increased awareness has served to make me a better rider because I can't be as sloppy as I was on the GS and KLR. To be fair though, I did quite a bit of great adventure riding on the GS and KLR, but I was trying to ride them outside their optimum performance envelope. Even the EXC is a real handful on a trail like the Rim Trail in Cloudcroft, which is 30 miles of rocky, wooded, and steep single track. There I was really wishing I was on a 250 or something instead!
I've not yet ridden a newer 500 EXC, for good reason... I might decide I can't live without it and I really don't need to be buying one right now. That said, my 530 is an absolute blast on the twisty bits of pavement. I've ridden it in places like North Carolina where the roads are crazy tight and twisty, and it was more fun than a sport bike on the same roads. That was even while running full knobbies. The lightweight and serious power make it intoxicating when shooting out of a corner, flipping it over, and setting up for the next corner. Top speeds aren't real high because there are rarely any straight sections, so it is all about acceleration and braking. The brakes on the EXC just blow away the KLR brakes, as does the suspension. I am no stranger to flogging a KLR through the twisties, and it is fun, but there is just no comparison. Rsquared and I had some fantastic rides chasing each other up and down the Blue Ridge, him on his 450 EXC and me on the 530. I can also run 75 mph down the free way through a busy city like Phoenix while fully loaded down and the bike is totally stable. No twitching at all.
Sometimes the twitchy thing can be the result of the suspension not being setup properly. My KLR was REALLY soft on the front end and the previous owner had the steering stem nut loose. I almost crashed the bike just going about 60 mph in a straight line. Properly torquing the steering stem nut, putting in slightly stiffer fork springs, putting in slightly heavier fork oil, and then setting the front/rear sag made a massive difference in the handling of the bike. If the suspension is not set up properly, that can have a big impact on the geometry of the bike and its handling.
I know there are a lot of riders that swear by steering dampers but I have never really felt the need for one. It makes me wonder if maybe some folks don't have their suspension set up right? Of course, for serious racing I'd probably have one, but I don't race. I do like riding in deep gravel, sand, and silt though. There have been some times when riding in really rocky situations where I would have liked to have a damper installed to handle the side deflections of the front wheel when it makes a glancing blow on a rock rather than just rolling over it.
A BIG factor for me wanting the 500 is the fuel injection. When my 530 is properly jetted and not clogged by nasty alcohol laced fuel, it runs like crazy! But if I let it sit more than a few weeks without remembering to either drain the carb or to put in Stabil, it is a real pain to get it running well again. Typically I have to pull and replace the idle jet because I just can't ever seem to get them clean enough with wire or an ultrasonic bath to work well. They are cheap, so simply replacing them is not a big deal, other than the hassle of getting to the jets. I had very similar issues with my KLR. My fuel injected 1200 GS does not have these issues.
For a few years, I had my KLR and a 1200 GS. That is a common combination. However, for me, they were just too similar in what they could do. The GS can do the rough stuff almost as well as the KLR but blows it away on the pavement. The KLR was not really suited for the more technical riding I was wanting to do, so the 530 just made more sense. If I want to run dirt roads, forest service roads, and hit the highway, then the GS is perfectly capable of that, even two up. But, when I want to ride stuff like Moab, the high passes of SW Colorado, some single track, etc,... the 530 does it all WAY better than the KLR. But not everyone can have two bikes, in which case the KLR is a great choice as long as you recognize its limitations. For most any riding you might do in Texas, other than single track trails, the KLR will get it done just fine, as would the GS, or the AT. Something like the 530/500 would be what I would choose for places like the Big Bend Ranch State Park with its really rough and steep two track "roads", or going to places like I mentioned above.
So if your question is whether or not you will enjoy having a 500 in addition to your AT, I would say a definite yes IF you plan to be riding stuff that is much more technical than dirt roads and/or single track stuff. I've done the week long camping trips off my 530, and I may do it again, but I think it would be more fun to base out of the same location each day and just ride loops out and back so I would not have to carry the extra weight of all the gear. So I would head down to Mexico on the 530 and stay somewhere like Galeana, riding for a week or so, then riding back home. I probably would not take it for an extended open ended trip where I am constantly on the move for more than a few weeks.
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