GPS, once mastered (to the necessary limited extent - I did it, and I have no interest in technical stuff for its own sake, purely as a tool), is incredibly liberating and IMO adds more to the cycling experience than a new bike is likely to do.
Just not needing to stop and ponder the map at junctions is wonderful, especially if like me you have 51-year-old vision. Staying away from main roads, but making steady progress towards your destination, is most excellent. Having confidence that you will not get lost is great. And you can "get lost" on a whim if you want to, and the GPS will get you unlost when you've had enough.
I have had great success with a Legend Cx, Tracklogs for UK route planning and Garmin mapping (on the PC) for trips to the Continent. I use the compass arrow screen. With a little experience, it is easy to interpret what it wants you to do at almost every junction.
I find the Garmin mapping a bit hard on the eyes for route planning, certainly compared with Tracklogs OS Landranger PC mapping; and it does not distinguish (in the version I have, anyway) between fairly busy B-type roads, quiet minor lanes and farm tracks. So for Europe I prefer to do the planning on paper maps (I still like maps), and then create the route in software. This works well for me because I tend to do centre-based tours, so don't have to buy lots of paper maps. Web-based mapping might be a viable alternative for planning, but like BTFB I am disinclined to mess about learning how to use umpteen different bits of software.
One other caveat: the instruction manual provided with a Garmin GPS is IMO simply not good enough for such an excellent and sophisticated device; I find it poorly organised and inadequately indexed. But there is plenty of cycling-specific guidance to its use on the Web, and plenty of advice available here and on other forums.