Tried 'em both, IIRC Yalp didn't work, Aurora seemed fine.
Since it was a banking app, I got the APK of many different sites/programs and compared the hashes, and one of the programs had definitely tampered with the APK, but I can't remember which.
Since I left Aurora on my phone, they seemed to have passed on untouched APKs, but don't take my word for it.
EDIT: Also, this voids me of any "warranties" my bank would offer me, so I'm really not going down that path. Really, the only correct thing would be for the bank to offer the APK on their site, but I'd probably have to wait until the government forces this to happen (if ever).