For people who don't want a GPS, I'm not going to work to convince you to get one. You like what you like and that's good.

I very much like having a bike GPS. I like to be able to see exactly where I was and see how well (or poorly) I'm doing on the same hill I climb. It's also useful for getting back home (as I can look at the bread crumb trail).

I have used my smartphone to record tracks too. It works pretty well, except (1) battery life (and i really want to make sure my phone has juice so I can call for help when I do something stupid) and (2) I don't have a good way to mount it, so I can't watch the numbers while I ride. I also very much like having both cadence and heart rate (particularly for looking at how well I'm climbing hills).

Cheers,
Charles