I see what you're saying. I don't think it's a good strategy to individually target a specific device. There's quite a few methods that will return the screen and viewport values consistent enough with @media to set breakpoints that should work on every computer and device not using an ancient browser.
In my case, since I'll already be using jquery for other parts, I could leverage $(window).width() and $(window).height() to tell when to switch.
This is your product and I'm pretty certain you're more knowledgeable in this area than I am, but it seems like the way you guys are determining when to switch to small screen mode is an older way of thinking that is not consistent with all the new devices currently out and that will be coming out.
Thanks for the info Steven ... I'm going to take a look at some other fully responsive solutions first and compare them to Juicebox before I decide which way to go. Thanks again.