i have only interviewed at Penn once (for residency)_ from what my cardiology friends tell me, its pretty high volume and uber-strong in EP ( Marchilinski, Epstein etc). Other specialities are very strong to excellent. The fellowship is quite busy. Moreover, there is little hand-holding in terms of mentorship: if you know what you want to do and go for it, you will be fine.. but ain't that how most 'big' places in cardiology tend to be (with brigham, mayo, duke being few exceptions).
i have not seen a lot of penn fellows being as well published as ppl from duke or brigham.
Nonetheless the program is outstanding for clinical training (like 20% other programs in the country 🙂 ), but has the brand name recognition. Clearly a top 10-15 program, some may argue a top 5 clinical program..