I like to use a regular bike computer and supplement it with my phone for finding services, evaluating route options, and so on. I do not want to have to keep a phone charged while having it on all day, so I only turn it on when using it. The battery lasts a long time if you only turn it on once a day for 10 or 20 minutes.
I advise against GPS with built in battery and will only use one that takes replaceable batteries. I do use a GPS on some trips but not most of trips. If I am planning to be off road a lot either riding or hiking I am more likely to use a GPS on a road only tour I do not. When I do I carry a few extra AA batteries.
I also advise against wireless bike computers. I know that the folks I rode with who used them seemed to constantly be finding that they had logged miles while they were parked near a neon sign or other interference. It did kind of even out with the times interference from power lines or whatever caused them to lose mileage while riding, but was still annoying. I'd just go with a nice wired one. I like the Planet Bike models, but have also had good luck with Cateye.