I had two small hickups, though. Firstly, by default the sql databases created by this extension use a latin-swedish collation, which caused problems with greek characters appearing as question marks (???). I had to manually change the collation of the tables to utf8-general-ci. Then everything worked fine. Not a big deal.
The second problem is that i do not recieve any mail notifications when someone submits a testimonial, probably a thing with my server. I am looking into this trying to figure out why.
Overall, a definite 5 star. Good job!!