Color me 'old school' then. I don't care for them. To me, they're just a version of the old back-stab connectors that are on the back of resi devices, and in 2000 they changed those to not accept 12. Hmmmm. Maybe there was a reason for that. Like they aren't good connections for anything over 15 amps. But here everyone is stuffing 10s into them new-fangled Wagos.
Call me old-fashioned. (My cell phone does two things: it makes phone calls when I push the buttons, and it takes phone calls when it goes "Ringy-Dingy!". It has a green screen. No 'net connection. No email. No text messaging. And it does me juuuuuust fine!)
I once did a house full of can lights that had the Wagos pre-installed in the j-boxes. OK, I thought, I'll give 'em a try. When I went back to trim, I had to spend two days pulling cans down in order to find the open connections.
Now, I know what you're thinking..... "installer error". One or two, I'd be OK with. But scores of 'em? C'mon! I had more loose connections trimming those cans out than I have the rest of my entire career.
Gimme a pouch full of tan twisters and my 9-Kliens.