I helped a random cyclist in the LBS get his Lezyne Mega XL to pair to his phone. He had been trying for several days. The menus are even less intuitive than those on a Garmin.
Sorry, RTFM.
I'm happy with my Lezyne Macro, but I got a new HRM this week and I had a tough time pairing it. Then I remembered the first HRM I set up - I followed the manual. THAT was a piece of cake. I, too have trouble remembering some things about the Lezyne menus. They probably made sense to the designer.
With a budget of $100 and a desire for real-time HRM data, I looked at Lexyne, Bryton, IGPSport,the Wahoo Mini, and used stuff (ebay and craigslist). The Macro came in at $74. The prices people want for their used computers are mind-boggling, so high that I can't imagine coming to an agreement with a seller. The Brytons mainly came from Taiwan and have their own problems. The IGPSports mainly came from China. Long waits for shipment. If I had problems, well, I've forgotten my Chinese. At least Lezyne is in California.
The $220 (including sales tax) Lezynes come with Open Street Maps and do more than similarly priced Garmin and Wahoo offerings. If my budget were $200, I might take a chance on one, but if I could stretch to $275, I'd find it hard to choose between the OSM on the Lezyne and the market dominance of Wahoo or Garmin...or the Bryton 450 or the IGPSport 618.
They all have their problems. I hope that, whatever you get, it works well enough to exceed your expectations.
My Macro has been trouble free, but I've had it only for a couple of months.