Rated 5 out of 5 stars
I think adding a Tab key is enough. Of course, giving a choice of customization is best.This review is for a previous version of the add-on (3.1.1-signed.1-signed). This user has other reviews of this add-on.
Please do not re-review again and again :P
Use the github page http://github.com/scrapmac/Auto-Complete for discussions etc.
I considered a preference because some people might want to have tab to complete feature.