My garage door opening is 6' 10" (lower than most). I just went through this process on my '03 VLX, and here's what I decided:
I eliminated the Titan II because the walk through window rests on tower when open, and there is only marginal ability to clear my garage door @ 6'10". I was told I may need to remove the tow spool each time.
I eliminated the Boss Billet because the "double" joint that allows tower to fold forward looks poorly engineered, but even more, the top bar seem very low to accomodate speakers and bimini.
I chose the Skylon Low Profile Swoop. This is a bolt-together after-market tower. It is solid, accommodates speakers and an after-market bimini, and fits easily into my garage while still attached to my tow vehicle.
An ironic note, the Skylon bimini doesn't fit under the Skylon DeafCon III speakers. Who'd have thought!
I need to update my profile pic