I saw this thread when it was posted, and I've been watching since in hopes that a customer would respond. As a company representative, I prefer to stay away from assesments of our cars because my answers are usually (and understandably) seen as biased. People haven't reponded, though, so I'll try to be as fair as I can.
I think the biggest disadvantage of the mid-motor layout is the same as one of its strengths: its different. The car requires a different driving style to become faster. Rather than coming into the corner straight to the apex, braking and pivoting the car around, and then punching it out, the X - 6 excels when driving smoother, broader racing-style lines and working to carry corner speed. If you try to drive it like a standard-layout car, the rear end can want to step out as you get back on the throttle, especially on a slippery-er surface. By adapting to the smoother lines, though, the X - 6 can carry more corner speed, require less acceleration out of the turns, and I really believe is overall faster.
Driving the X - 6, you don't realize how much extra corner speed you have until you start racing it with other traditional cars. When you're driving it by yourself on the track, it sometimes doesn't feel especially fast, and it can feel loose coming out of corners on slippery tracks (see above). But then you start a race with 9 other cars, and unless you adjust you literally hit those cars on their motor guards on every corner! I've heard similar statements from customers all around the world, of all skill levels.
Probably the best thing I could recomend is approaching someone with an X - 6 and ask them about it. Ask if you could take it for a few laps. Try it for yourself - I'd like to think you'll be impressed.
__________________
|