Yes, SDs are allowed - but only in the accessible (wheelchair) vehicle. So, go to the accessible line when it splits off to the right side while everybody else goes to the stairs to the left side. You may have to wait longer to get on the ride, depending on how many ppl in front of you in the accessible area (if any) need the accessible vehicle.
While the car does spin when changing from game to game and coming back into the accessible loading area (a caution for those who are ultra-sensitive to motion sickness), an SD doesn't get bopped around like you might think.
Like with every ride, some CMs may try to demand that you make the dog lay down. This is one of the rides where you should allow the dog to choose the best position.
If you have trouble pulling a string to fire the guns off, sit on the right side of the accessible vehicle, where you can hit a button on the top of the gun to fire the gun. For me, pulling the string constantly would very likely bring on my wrist pain (I tried the string, the pain started, so I immediately stopped and thankfully the pain went away), so I was still able to play the game by hitting the button with the bottom of my palm (the boney part just before the wrist) while keeping my hand straight - no pain!
It is a GREAT ride!! I highly recommend it.
My SD couldn't appreciate the cool 3-D effects, of course, so likely wondered what the point of the ride was! We rode it three times.