There are certainly many things to like about the GG (I have an '11 300 6-days) but it's far from perfect and in my mind not a clear winner over a KTM, it really depends on what you're looking for. Skill level, riding style, and type of riding will factor into which bike makes more sense for each potential new GG owner. These are the factors that I think apply (having owned 5 KTMs and one Gas Gas):
KTM:
1) Better components (brake lever, shift lever, chain guide, kickstand, etc..)
2) Better quality of construction
3) Set-up suits a wider range of conditions than GG (i.e. suspension, motor, and carburetion of KTM seems to work reasonably well most anywhere or can be easily tuned to do so.)
4) Wider range of accessories and more vendors
Gas Gas:
1) Better handling
2) More powerful engine
3) Costs less
The biggest frustrations I've had with the Gas Gas so far are:
1) Awful suspension set up for riding in hard pack rocky terrain. Needs re-valve right out of the crate! No amount of clicker adjustment could fix this problem (I'm a 50 y.o. B rider, your experience may vary!)
2) I spent a lot of time fiddling with jetting and powervalve adjustment to tame the "hit" of the very powerful GG motor.
3) Gas mileage is lower than any comparable 2-stroke I've owned (15%-20% lower than my 2007 KTM 300). You'll need a large gas tank almost immediately.
4) Strange bolt sizes and generally low quality fastener hardware.
Don't get me wrong, I love my bike now, but I've already spent $1700 and 9 months of tuning to finally get it to the point where I can honestly say this! I have no regrets in buying the GG, I just wish it were set up better from the factory and that there was some way to easily trade power for fuel economy.
Steve
! Collecting intel for a new ride ? 
