For many years I always used whatever version of Garmin's Zumo GPS. Finally I decided I'm done. They are expensive, have poor visibility in sun light, and a true PITA when in isolated situations where the road disappears if you zoom out. I planned to keep the Zumo 665 until it died then go to a phone. Even though my early experiments with a phone were mixed at best. I found I had a lot of uneasiness with the dust, the weatherproofing, and the insane amount of vibration when riding off road, and of course the inability to adjust anything unless wearing fingerless gloves. All of that even before finding a suitable mapping app.
My attitude changed when on a multi-day ride with a trusted riding buddy and he could not stop highlighting the improvements Garmin had made on the new Zumo XT. It really was daylight readable (for the first time), they dramatically improved the map operation, included map updates in the purchase price, and the price was significantly lower that previous versions. This friend's recommendations had a long established, proven track record with me, so I took the plunge. Good move on my part.
The XT is a game-changer in the Zumo line. It doesn't suck. I'm hard pressed to come up with navigational changes I would make. I think Gramin realized they were losing out to phones and had to come up with a justification to keep selling GPS units to motorcyclist. They bought themselves a few more years in the bike market. It's not perfect. The cell tower driven weather info is limiting in areas without cell towers. There are times when getting back to the navigation screen takes more screen touches than I'd like. And of course, when you have a phone, a headset, a gps, and maybe even a bike with bluetooth, it all can go to sh!$* and make you want to turn off everything. But overall, the XT is a great step in a positive direction. Garmin has preserved a spot on my bikes for a few more years.