Vivoli is one of these places that doesn't really stand out either way - but this is a problem on a street like College where you are competing with some solid restaurants.
Service was particularly slow on the Saturday night I went there on a date. We ordered 2 beers and 2 dishes and we were there for almost 2 hours. The very few times a server came by it was a different person.
We weren't in a particular rush so we didn't mind too much, but I can see how that would be problematic.
I've eaten at Vivoli's many times over the years and have always felt ok about it, never super overwhelmed with enthusiasm.