We finally made it to Blue Horseshoe on 20th street (near Chestnut) this weekend. We arrived on Friday night around 6:30pm to find it very lively and almost full with happy hour crowds. The space is designed as "modern pub" style, with big windows that open during nice weather.
We ordered a couple of drinks which were well made and inexpensive ($6.50 each for an Absolute martini and a Cosmo) though I don't know if that was happy hour or regular pricing. They also had a good selection of beers on draft (Hoogarten, Yards, and about 8 others)
We each had a Caesar salad as appetizer. This was one of the tastiest Caesar's in town, with great fresh garlicky and anchovy dressing. It was served in a "parmesan crisp bowl" which was a little tough to attack with a fork, but had good flavor.
I had a filet mignon sandwich ($9), which had good-sized chunks of steak rather than a solid sandwich-sized piece of steak, but was very tasty with caramelized onions and provolone. The side of fries were good, hot, and crisp.
The Bride had a tuna steak sandwich served rare, which was very moist and with a good sauce with greens on a soft challah roll.
Dessert list was disappointing, with just a few varieties of cheesecake, so we skipped it.
Overall recommended for happy hour and/or a casual slightly-upscale pub dinner. Their entrees were $16-22.