I have used various extensions by Gavick over the past years and they are usually VERY good. I don't want to say that there weren't any flaws here and there but in my opinion Gavick is top of the notch and they seem to get better and better.
Btw, so far I have only used Gavicks free stuff and I thought after this great experience it's time to say THANK YOU to the Gavick team for taking away loads of my headaches over the past years.
P.S. Regarding the earlier review: Version 1.22 works fine for me in IE 9 as well in any commonly used browser. I'd recommend you have a look at your template css.