The details about studying abroad in London are what makes this really worth reading. Travel, dorms, even shopping for groceries at Tesco are all things that would have been completely enthralling to me when I was in high school or early college. It's even better that Shane is happy about being in London, since too many books involving foreign exchanges are a bit whiny.
As an adult who understands Shane's father's reluctance to pay big bucks for a creative writing degree, I found it a bit hard to understand why Shane was unhappy in 2017. She'd made it through the hard part of medical school, she had a serious boyfriend, and we can assume her parents are happy with her. She wants to throw this all away to go back to Pilot, who wants to be a musician? Not quite getting this situation, but certainly can understand wanting to go back and change the past!
Readers who loved the time travel in Mlynowski's Gimme a Call or Asher's The Future of Us, and who want a college aged protagonist who just wants to be kissed and have a beer or two at a pub will enjoy Again, But Better. Maybe it will even help them get their life right the first time around, since we really aren't given second chances!