My wife and I have used all three - Semax/Selank together and Pinealon separately obviously.
We inject Semax/Selank 1mg each daily in the morning for 4 weeks on/2 weeks off cycle. We get improved focus when taking it and miss it when we're not taking it.
We've used one 20-day cycle of Pinealon. The effects of this one are subtle at best. The only way we were able to quantify its effects were based on Apple Watch sleep data that showed an uptick in nightly deep sleep time after 5-ish days.
I've posted this link in another thread, but I'll share it again. All three (and others) are talked about in this from Nick Trigili. After you get past the "bro"-ness delivery, he made a lot of sense to me. We tried the entire run as he described with maybe a little more on the Semax/Selank combo and injected instead of his suggestion of nasal application. https://www.youtube.com/watch?v=MyTP0qz8R4s&t=307s
That's the short of it from our experience. We'll continue to use Semax/Selank and run a cycle of Pinealon twice max per year.