I have a Bryton 530. I got it because of the price (MSRP $180) and above all the battery life of 34 hours. I also have a Garmin Fennix i horse traded for used. I have been watching the Lezyne mature hoping they would get to this state and am excited. I love their other products. Looking forward to trying this IF it does do turn by turn decently. I have used many GPS extensively in the field including a Garmin Dakota for doing 1500 miles of the great divide. It ate a set of lithium AA batteries every day and a half of riding. Am not a fan of garmin because of the short battery life and their tendency to crash. The brytons are by no means perfect. For one they only do a line follow of the route with no street names or base maps. I hear a newer color version with possible base maps is shipping here in the US soon though. Having traveled/toured extensively with people using various navigation devices they all have their pros and cons. Even the brytons lock up for example, but they very quickly can be restarted and can get back on route. This has only happened to me twice. Garmin lockups seem to happen much more frequently on the 520 and 800 series i have experience with and often you cannot get the route back up. That said garmin are still the best for complex navigation jobs with street names, base maps and audible turn warnings, but to often they have left me stranded and having to pull out my smart phone. Ultimately for my touring purpuses I need complete reliability and long battery life. If that mans trayscale screens and simple line trace routes I can deal with it, but it does occasionally mean pulling out the old samsung S5 with Gaia GPS software on it. My garmin Fennix is the same way. No base maps as it is last gen, but great battery life and basic navigation.
P.S. love the signature: "Randonneuring -- it's touring for people that aren't smart enough to stop for the night. It's a wonderful sport when you can make up for a lack of ability with a lack of sleep."
I have settle down more now that I get to tour with others. Less riding around the clock, but getting to tour with my SO is amazing. She is not quite as adventurous as me, but not everyone likes to ride all night and gets excited about riding in blizzards.