Yeah, those look pretty low. I could definitely see the bike rocking up onto the tank. I've seen some that mount higher up, but closer to the bike, which would probably both protect better and make it more difficult for them to snap off. You may find this page useful. It's more keyed to the Ninja 650R, but most things should fit.
http://homepages.slingshot.co.nz/~shanetp/Sliders.html
I saw your thread about the crash bars. I like them, but they look like they would make working on the bike more difficult.
I needed the luggage for my commute, so that went on first. If you do decide to buy the luggage assemble all the brackets loosely first, then have a friend hold them in place while you get everything finger tight. It's a real pain in the ass if you're assembling it on the bike, getting everything to line up. It's good quality stuff and it does fit well, there's just an easier way to get it done than how I did it (alone and piece-by-piece).
I've already bought a Givi A446 screen, in solid black, and I'm just waiting for the mounting hardware. That seems to be a common theme with buying Givi stuff in Canada.