I had the opportunity to try one two weeks ago. I like it. It is a variation on the GLOCK idea, of course, but it is a solid pistol. The main difference that I see with this one is that the have managed to get most of the mush/creep out of the trigger. Mush/creep is fine once you adapted your brain to how it works (don't get me started on my diatribe on GLOCK, I love the GLOCK 19), but some people don't want to learn to adapt to that, so they design the pistol to try and get away from that. Which is good. Innovation and change is always good.
The trigger on the SPF9 feels a bit stiff to me, but I think you could learn to really use that to your advantage. I would describe the trigger as fairly stiff, with a more defined (than GLOCK) breakpoint, maybe a little shorter reset, and reasonably light... but in a "stiff" way, if that makes any sense. Hard to describe in words. It is an accurate gun though. I was beaning stuff right on the nose with the first few mags. Bullets landing generally no more than an inch from where I wanted them, and lots of them cutting ragged holes with the previous holes in the target, so that was encouraging. The HK-style sight set-up is probably part of that (front dot covers the bullseye), since I am damn good and used to HK style sight set-ups, as a P7 nut.
I had the opportunity to try the Walther PPX the week before, and I really like that one too. It costs half as much, and that is probably the best feature of it. The PPX trigger does creep a fair bit, but I was noticing that more on dry-fire than actual shooting. During actually shooting it felt really good, and was accurate. I didn't get quite the accuracy out of the PPX that I was getting right off the bat with the SPF9, but it was more than acceptable. Finally the other gun makers, 20-30 years later, are catching up and making a striker fired pistol that rivals the GLOCK. Of course, for me, none of these guns can hold a candle to the true classics like the P9 and the P7, but you can't make one of those guns (roller-delayed or gas delayed) at this price point anyway.
I eased the slide into battery in this video for some reason, and that is me feeling around on the break-point of the trigger here too. Maybe not the best video, but I was literally just putting a couple of mags through a buddy's gun to see what I thought.