Didn’t notice the difference between new Testimonials element and old Quote element.
By the way, in quote element you can choose from many options in graphic setup such as graphic border radius, box shadows etc, but in new testimonial element there is no this options in graphic tab.
So i can confirm that new Testimonial element is a trimmed Quote element. Sad 
Hi @Georgich,
You’re right, it’s very similar to the Quote. The main difference is that it doesn’t include the “Marks”. The idea is that it would be a more simple element to use because the Quote is has so many options.
You can still customize the graphic stying though. It’s just not part of the Citation. There’s a control group called Graphic with the controls you’re looking for.
Wanted to post an update here. Beta6 has a revamped Testimonial element 
and we’ve also added a standalone Rating element as well.