I've had some on the best bike for a while. They are tubeless, 25mm version. I am running them at 80psi
Had a sidewall puncture (that didn't seal properly, probably due to high pressure) last night. That was the only noticeable puncture
The feel of the tyres is pretty much how I'd expect. They are a racing tyre, slightly heavier than some but really flexible (read: comfy), grippy and fast
Dunno how many miles I've done, the bike was out of order for PBP but the tires did a 300km in July
I have not previously been a gp4000 user.
Might try the GP5000 28mm (or larger? is there a 32mm version?) at some point
I bought the tyres from here
https://www.deporvillage.net/continental-grand-prix-5000-folding-road-tyre-black as they were a few months ago a lot cheaper than other sources. Seems to have evened out now, there's more people offering them at around £37 sterling*
* sorry missed the "here in Canada", no ideas on tyre suppliers in Canada!