I have owned the GPS with speed and cadence option, plus heart rate monitor for about 1 1/2 years. Many have already mentioned its long battery life, which it does have. Also, three screens can be customized to display what YOU want to see which is really nice. Others have mentioned the design is box like, but who cares?
While I have been cycling for about 30 years and have had many bike computers during that period, this is my first GPS. Overall, It hasn't lived up to my expectations and at times it has just not worked properly. But, in fairness to it most times it does. But, even if it is once where it fails who likes being lost because their GPS doesn't work properly? More than once I have used Google maps to bail me out.
Once off course you get a screen that looks like it was drawn on a miniature Etch A Sketch which might have been impressive 10 years ago, but not so much today. You don't get instructions to get back on course.
Lezyne sends new versions of the phone app and GPS every other month or so which speaks to its bugs.
Cadence and speed have worked flawlessly.
HR monitor is accurate, but the battery showed 80% life left before it went dead. Also, HR monitor didn't synch to GPS one time and I contacted support and learned there is an ADDITIONAL app just for that problem. Again, it speaks to the bugs.
Support has been sorry. One time I designed a course that zig zagged through several additions. The goal was to have a respectable length ride without getting on highways and there were a lot of turns. At the start, the GPS said my next turn was in 3 miles even though I knew there were many turns before that. Support seemed helpful and empathetic at first. At their request I forward my .tcx route file. After looking at the file, the support guy chastised me in an email for making a route designed to make the GPS fail. WHAT???
Their web site is awful for designing a route. Fortunately, you can import .tcx files from mapmyride.com
I hope there are better GPS out there. This one is not too expensive, but it is also no too good.