Time for some number testing with the new Tomes.
Fresh level 4 character right off the boat.
Lesser Tome of Learning consumed, 10% exp pot consumed.
Quest: Bringing the Light Normal, first completion
Screenshots follow (at lowest game graphics trololol)
Pre-completion 1/2
Pre-completion 2/2
Post-completion 1/2
Post-completion 2/2
Base exp: 298 exp
One level over: 269 exp (-10% base = -29 exp, correct)
First time bonus: 343 exp (+25% base = +74 exp, correct)
Tome bonus: 475 exp (+45% base = +132 exp, not +25% = +74 exp, incorrect)
Upon completion: 522 exp (+10% pot = +47 exp, correct)
Edit: Math on tome is showing 10% bonus from flawless and Persistence in calculation.