I took a 2 day intro/level 1 carbine course from VATA this spring and it was perfect for me. I shoot a lot of pistol, but literally had less than 200 rounds lifetime through and AR. I basically walked in and said "I don't know crap, teach me". At the end of day one I felt like I just wasn't getting it. With some dry practice in the hotel room and another day of work I was able to do really well in the end of class "competition" and felt MUCH more comfortable with the platform.
One word about the "I've got my own range" comments. So do I, but if you don't get some feedback it doesn't mean there is not a better way. I've taken things from each class I've been to. Even if it's that I don't prefer what they taught and it affirmed what I'm doing otherwise.
I took a two day course awhile back. I liked the two day format better if you're some what experienced. Like someone said above, one day course for those new to shooting /handling a firearm is an excellent idea. They had a couple in our class that where brand spanking new to firearms and they kinda slowed the class down because they required more attention from the instructors.
I have taken from Advantage Group and VATA. Both groups are close and were very professional. I have only been to one other traveling instructor, but they compared very favorably. I also spoke with some guys in the VATA class who had been to LOTS of classes around the country. They told me that they felt the quality and student/instructor ratio with VATA was excellent and better than some big name guys they had been to. Just FYI.