I didn't want to comment for a couple more days, as I'm in the process of having the Viper Smart Start installed on a 2010 RX450h. They've had some problems, but want to wait till we get it done right or rip it out before I commented here. However, I will say this: the factory remote was $375, although I don't know who or what the factor remote start is, Directed or what.
I do know the distance on the factory remote is less than satisfactory. If you have used a remote with some distance capabilities, the 30-75 feet the factory remote works will seem very lame. If you like standing at your garage door and starting your car in the garage, the factory remote is for you. The $600 seems high, but I guess not too uncommon. Check the distance before you order it.
Also too, check to see how the car responds when you get in after remote starting. On a 2010 RX450h with a factory remote, with the car remote started and running, when you approach the car and unlock the doors, the car will stop running and you will need to restart it when you get in. A small pain in the neck. This is not how the Smart Start works in my wife's Nissan Maxima. With the car running after remote starting, you unlock get in, don't touch the brake pedal, and then touch the start/power button twice and you are ready to go. Engine keeps running. These actions are, of course, for safety and prevention of theft.
Also as more computer tech is in the cars, third-party remotes must work well with the computers in your car or it won't work consistently or you'll get errors in the car. Make sure your installer has done your style and age of car. Ask for references of cars they've done and check with those folks to see if they are happy.
Good luck.
