We had breakfast at Pamela's on Walnut Street (Shadyside) on a Friday in October 2016. We arrived before 8:30 AM and there was no waiting for a table. By the time we left at 9:15 there was a line. Service was fairly prompt but a bit slow with coffee refills, as other reviewers have noted.
The cash-only policy, announced by a sign near the entrance, was an unpleasant surprise, and on most days would cause us to move on to another restaurant. But on this occasion, driven by hunger and strong recommendation from our hotel, we decided to stay. Two of us ordered the "morning after" breakfast special, one of us ordered a waffle, and one ordered pancakes plus a side order of strawberries.
The food was good, but standard diner fare. The pancakes are touted as "crepe style," and although they are different from pancakes elsewhere-- thinner than classic pancakes but heavier than true crepes-- that doesn't necessarily make them better. Cash-only is often cited as a way for restaurants to keep their prices low, but the prices at Pamela's are actually on the high side for a diner.
Although the dining room is wheelchair accessible, the restrooms are not. They are located upstairs, at the back of a different restaurant.
On balance, it's hard to see why Pamela's would be worth the extra inconvenience of cash-only and a possible long wait in the vestibule, when there are so many other restaurants serving similar food without the disadvantages.