OK - so
this is the exact one we are using currently; I have one for each vehicle our family owns.
A couple of notes: We always remove the weird little cords that go through the grommets; we have never had a use for them, and they just get in the way. We leave it installed (see the last picture) and it folds easily between uses. The velcro goes all the way across to make it secure.
It does not go all the way across the back of our ginormous Kia Carnival van, so we just installed it on the side that we tend to load the wheelchair on. When we travel overnight, we stand it up on it's side and keep it securely in place with bungee cords. That way the chair doesn't take up the entire cargo area, and it prevents it from sliding around and possibly getting damaged.
Another note that we haven't really talked about, but many of the chairs in the "lightweight" category will require you to have the battery in the chair to charge. That came as a surprise to me; I was used to my TravelScoot, where I could leave the device in my vehicle, and just bring the batteries in with me for charging. Also, it has been interesting to see how long some of the chairs take to charge; one of my chairs charges at a fair pace, while the other is slower than I had anticipated, and can take a full 8 hours to reach a complete charge. Just one of those little surprises that I never considered before I got my first chair.
One last thing to remember about any of the "lightweight" portable chairs that many of us are using now, including the Falcon/Eagle, the Zoomer, and the Fold & Go: These chairs can still be difficult to load and unload, depending on your personal circumstances - They all weigh at least 50 pounds, and the Magshock is 60 pounds with it's batteries installed. I would *strongly* recommend that anyone who will not have help make sure that they can load and unload by themselves prior to purchase. As I have said before, I can no longer stand unassisted long enough to load or unload my personal devices myself. Standing long enough to set up the optional power lift for the Fold & Go is out of the question for me; it's very clever, but I can't use it. People who have a sedan with a traditional "trunk" (instead of the rear cargo area so common in the back of mini vans and SUVs) may have an even greater struggle, since the chair will have to go up over the lip of the trunk, (and try not to damage the weatherstripping) be placed down in the trunk for transit, and then have to be dragged back up out of the trunk at the next stop.
If you don't know anyone (locally, in your area) who has a power chair of a similar size, I would try to go to your local mobility equipment shop/dealer, and ask them to show you their lightest chair (find out what the weight is for comparison purposes) and then ask them to demo how to get it in and out of your vehicle safely. Before you make a big investment, make sure that you can actually get it in and out of your vehicle; it's important!