The Owl & Firkin is a popular place for a weekday lunch with the office buildings nearby. The food is consistently very good and seems to be of a higher quality than most other Firkin pubs. They have two patios, with the rooftop one definitely being the better of the two. However, they can fill up fast on a Friday afternooon, so get there early if you want to enjoy the breeze.
The service is average, though we've once had an issue with them screwing up the bills when we were there as a large group. It only happened the once so it's not the end of the world.
One negative point would be that their upstairs bar isn't a complete one so frozen drinks aren't an option on the rooftop patio.
One tip: You can turn any of the salads on the menu into wraps, giving you a more healthier options than you'd think.