Harris was one of the places I first visited when moving to Pittsburgh. Its another place that should go on the list of places that I've had mixed feelings about.
I had originally mainly visited during the happy hour, but to be honest the happy hour is just alright. $5 cocktails and apps, or something else not super memorable. The drinks are good and the appetizers are nice, but small. They usually have some type of frozen drink option, such as a frozen cosmo or mojito. I've had the hummus multiple times and it comes with a nice spread of vegetables and is a pretty good size.
I had gone for brunch a few months ago and was actually really happy about the food and service. I went for the brunch buffet and was actually really impressed. They didn't have a ton of vegetarian options, but they did have a create your own omelet station in which my omelet was cooked in front of me. They also had the best breakfast potatoes ever. And a good assortment of fruit and mini bagels with lox.
The servers are pretty good and most places you can be seated are nice, besides the weird window seat which seems nice at first, but is a hard place to converse due to the only seats facing one direction (instead of facing each other.)