GPS is a big time saver. Route finding’s not terribly hard, but if you stop to check the map every 5 miles, or more often at some spots, it sucks a lot of time.
Really frustrating to pick up speed downhill and get that nagging feeling that, although you’re certain this is right, if it turns out you’re wrong, you’ll have to climb back up. So you haul down from 25/30mph, get map out, orientate yourself… yes, this is right, map back in bag, start rolling again.
And then you pass a fingerboard 10 seconds later, showing you’re on track!
Much more efficient to have a quick glace at the stem, yup. All good.
And an off-route chirrup to warn you when you’re off with 20 yards of a wrong turning.
Don’t know of anywhere that hires, though, but it’s worth having a computer with you anyway to keep a track on pace and time. You can spend £20 more and get one with a GPS trace and an off route chirrup. Edge 20 or something.