Hitch mount tray style bike racks are by far the best and safest option for carrying your bikes around. If you've spent the money for a nice bike, you don't want to use a cheap rack and risk losing it on the highway. Roof mounts are ok until you forget the bike is on there and pull into your garage. Also, nobody wants to put a 50lb e-bike on their roof rack. I've used a bunch of these and this one from Kuat is the best I've found. The combo foot/hand lever for moving the rack to/from the upright position is awesome. It's so much easier than the pins you have to pull out on other hitch mount tray racks. It's also rather easy to take on and off the hitch. It comes off in under a minute and goes on in under 2. If you have the extender on so it holds 4 bikes, you might need someone to help you since it's a little heavy. I really didn't think i'd use the little bike maintenance attachment, but it's come in handy at the trail a couple times when I needed to make some emergency repairs. It's not the cheapest option out there, but it's worth it if you're carrying expensive bikes. Although, if you're just carrying around some clunkers, you're better off with something cheaper.