Just my little 2 cents. I dont recomend a tegu as a first lizard, but obviously if you do your research and are prepared (and have a lot of patience ), then you will have a blast. Just be prepared for anything if you get one.
I dealt with angry monitors before getting my first tegu, and i couldnt believe how mean and nasty it was. Ive also seen very nice tegus that are calm. Be prepared and ready for anything.
Agreed, they will not always be "puppy dogs" mine can flip on a dime and shes not even full grown yet.
I've done a bit of thinking, and I'm probably going to go with either a chameleon or a skink. As cool as tegus are, I simply don't have the space. And also my roommate has a rabbit that she lets walk around the house, so a large, carnivorous lizard may not be wise.