'97 Grand Cherokee, FM-870 Commando

So about a year ago, I bought my gf an FM-870 Commando Alarm/Starter for her 2002 Jeep Grand Cherokee. All installation quotes have been upwards of $200-$500. More than I paid for the alarm. I really like the features in it so I am thinking about getting the same one for myself for my '97 Grand Cherokee. I figured, I will try to install it on my car first, and if it is successful, do it on her car. Does anyone have any thoughts on this type of Alarm. Should I invest another $200 for my car? I have never installed a car alarm before, but have confidence in my ability to learn. What kind of difficulties should I expect? Is this too big of a step for a novice car tinkerer? 

BTW, I also have a corvette that I may be interested in changing the security on in the future. I also have a firebird that I will be pulling a bad engine on (never done that before either, but have all the equipment) in the next couple of months, so I am not hesitant on taking on big projects as long as they are straight forward with minor issues or I can hit forums like this for help.