My parents got me the ProAm crane you referenced for Xmas this year (pretty nice present, eh? especially when all my other mid-20s friends got books and ties).
I have enjoyed it immensely. The shots I get with my GL2 are wonderfully smooth, and it really adds quite a bit of production value to any job (if not overused, of course).
You’ll want a quick-release plate for the bottom and some sort of monitor. I happen to have a portable DVD player from Best Buy (store brand) that works quite well for this. $150 + $10 in cables at Radio Shack. It doesn’t relay the color/exposure information perfectly, but it’s great to check framing.
You’ll also need a serious tripod to handle the weight. Mounted on my hefty Bogen tripod, I’ve flown it up to 18 feet, which is plenty high for most applications. If you’ve got a sturdy tripod, you can achieve steady results at such heights.
A caveat: It’s not quick-folding or anything, so you’ll need to budget 5 minutes to set it up and take it down before loading it into your vehicle.
Hope that was some useful info for you.