I find myself a frequent visitor of Howler's, if nothing else because of the good beer selection and the close proximity to my apartment (no worrying about finding a DD for me!) While I've only been here for brews and for shows, they tend to do a decent job at both.
Beer selection is impressive, waitstaff fairly friendly. The clientele is usually drunk and yinzery (albeit endearing). Major downside - Howler's has terrible ventilation so if you're not a fan of cigarette smoke, beware! I can barely stand to be in here longer than a couple hours at a time because of how bad it is. Also, their space is really narrow and small, which is fine when it's empty, but extremely annoying when it's not.
Major plus side: their sound is great! One of the best sound systems in PGH, for sure (in terms of clarity and balance). If you're an audiophile, you'll love it!