My quick answer is Yes to GPS, although it's not a no brainer by any means... If you're a long-term mapNcompass user, with a host of skills aquired over years of practice, and are happy using them, then the benefits of a GPS unit aren't obvious. The fact that the GPS records exactly where you've been might appeal. The fact that it will continue to monitor your position in white-out conditions / fog / darkness might appeal. But equally, the fact that mapNcompass don't need batteries might appeal too! When I used to do multi day cycle tours, I tended towards paper maps, because I couldn't always guarantee being able to charge a GPS every night...
Wlaking, I use a GPS unit and nearly always take a paper map with me as well, mainly 'cos I like to have with me a large-ish overview of my route & surroundings. The size of a screen-based view doesn't allow me that - at least, not at a zoom level I'm comfortable with.