I ended up going with that Scorpion tracking system and I have to say I am impressed. Pretty easy to set up - the hardest part of the install was getting to the battery. It's got tilt, ignition and shock sensors that seem to work well. It can be linked with their audible alarm system, though I did not get that (yet... not sure if I want the alarm or not).
Plus it's tied to the Rever app, which is a pretty neat app - from ride tracking and sharing to even setting up notifications for when I start or stop a ride. There's even a live link you can share that someone can click to see where you are in real time. Not something I plan to use much, but cool... particularly handy if you need to give it to the authorities in case it's stolen.
It's also worth mentioning that when I called support with questions the guy was very friendly and helpful; a big plus in my book.
Only down side I've found so far is the price - $250 for the unit plus $15/month for the data plan. That feels expensive, but for me personally that's worth the peace of mind.
I've had it a couple weeks now and it's working as advertised so far. If I come across issues I'll keep this updated.