I have the IQ as well and love it. I'm biased though, I'm an IQ dealer.
Here are some answers to your questions:
Which one: Neither CompuQuilter nor Intelliquilter will void your 8 year APQS warranty. That's a big deal.
Price Range: Intelliquilter is $12,500 for a self install. (APQS machines are a no-drill install). To get it installed you will need to pay dealer travel costs which vary as to how far your dealer is from you. You can find the list of IQ dealers here.
Pros & Cons: Intelliquilter uses a friction drive wheel instead of a belt system to push/pull the machine. (Both ways are very accurate.) Since IQ is on friction wheels you can simply move the machine with your body to the desired points instead of using a keybord/number pad to jog the machine 3" to the left. With IQ you just grab the handles and move it to the location you want and click in the point. You would do this when you want to move the machine to certain areas of your quilt to click in boundary lines- for instance to drop a motif into a block you'll move to each corner of the block and "click" in that location so the computer can size/rotate your motif to fit. It is nice to just visually grab the machine and move it.
I can also "trace" around an applique with my needle and declare the area I've traced to be a "no-sew" zone which prevents IQ from stitching out any patterns over my applique but it does allow me to drop in echoes, radiating lines or dense filler behind the applique with ease.
A cool feature with IQ is the ability to record the movement of your machine as a path that you can then copy/flip/paste to create your own patterns.
What I really like, though, is that IQ is not a Windows based platform or an Apple based platform. It runs on Linux and is, therefore, very clean. Plus, with IQ the tablets mounts right on the nose of your APQS machine so there is no hardrive tower/cables/monitor/keyboard. The little touch tablet that is mounted to the nose of the machine is the whole enchilada!
If you'd like to see a video tour of IQ mounted on an APQS machine click here.
I hope that helps! You can do a search on Intelliquilter on YouTube and see all the great tutorial videos out there. IQ is super easy and intuitive but it is always awesome to have lots of great free videos you can lean on as you get started with your system.
Obviously, I can prattle on about IQ at length. If you want more info, just U2U me or email me directly at Angela@QuiltedJoy.com
When are you going to be holding one of your online classes again for the IQ? I receved my in October and would love to take your online class but I work outside the house during the day.