Finally got my hands on a TP9SFX after following it since 2016. I haven't had a chance to shoot it yet given the weather but my first impressions are very favorable, especially given the price point of ~$400 street...if they can get quantities out to shops.
My only other Canik product is the TP9SA and that is where I will base much of my comparison/contrast. The trigger on the SFX is improved compared to the already good SA. I don't have a trigger gauge but the pull weight is slightly lighter. However, the biggest difference is the shortened reset which is considerable compared to the SA. This jives with what Canik has been promoting.
The extended mag release comes with three different size adapters. Four if you count leaving the adapters off and just running the stock release. The mag release is ambi.
The grip comes with two adjustment inserts, just like the SA.
It comes with four total adapters for micro red dots and they are the typical variety seen from most manufacturers. There is an included cover-plate should you want to run irons but the rear sight dovetail is integral to this plate. All my RMRs are sitting on other guns but I have a Vortex Venom on the way and the promo pictures of the SFX show mainly Vortex red dots, so they should be GTG.
Also included are spare fiber optic rods for the front sight in yellow and red. The rear sight is a Warren.
The holster was also redesigned as well to include a top strap. The paddle comes from the factory similar to the other TP9 lines.
Overall non-shooting impression is that this is an outstanding package for the money. I will update when I can get it to the range.