Rival Darksider here - favorite pistol out of all the pistols I own of any make/model. Best OEM striker trigger out there - even puts my PDP trigger to shame. Not just a great trigger for a striker gun, but a great trigger - period. Zero creep, crisp break at exactly 90 degrees, short reset. Factory match sights are outstanding with fiberoptic front and several different fiber colors provided with the included tool kit. Great texturing on both grip and frame. Full ambi controls if that's your bag. Accurate as hell, and my accuracy goes up the faster I shoot it. Fit and finish is excellent, zero slop anywhere I can feel, no rattles. Five frickin' optics plates including a cowitness plate.
Cons? I wish it was a little more front-heavy, and that there was more variation in the included back straps. Holster availability is nonexistent due to not interchanging with the TP9. Canik does not make it easy to find/buy their accessories. For example, the extended mag floor plates that come with the Rival for use with the flared magwell are not listed on their site, nor can I find a part number for them anywhere, and they don't come with any of the factory magazines.
If Canik made something the size of a P365XL with the Rival's trigger, my SIG and PDP compact would never see the light of day.
I MAY put a Holosun green dot on it, but am still undecided.
IMO, the best value out there right now in handguns. Something of that build quality, performance, and included accessories that's regularly available at $639? You can't touch that with a 20 foot pole.