In reply to iusedtoclimb:
Yep, they stay on. You need to make sure you get the right version (tailgate/barn door).
Don't do what we did and reverse into a lamppost a week after buying it...
Oh, we decided to take the opportunity to replace our gas lifters as the tailgate wouldn't stay open without the bikes on. We got uprated ones that now stay open even with 2 bikes on the back. Getting it back down can be a challneeg if you're small and light, like the girlfriend is!