After running out to see the vampires at the local lab [blood tests], I did a quick run through StylePixPro -- not bad at all Judging its capabilities I'd rate it at about 1/2 of PaintShop Pro, a bit less re: The Gimp, & about 1/3 P/Shop, hoping that that maybe unusual sort of rating is useful at all. That isn't shorting the SK developers, but patting them on the back once you consider the development hours that have gone into those other 3 apps over the course of many, many years.
StylePixPro itself takes up ~41 MB with all the extra language files removed. There's a 32 bit & 64 bit version of the StylePixPro.exe file but everything else appears the same. The setup file expands out with 7-zip, as long as you let it rename the duplicate .exe file, and if you have a reason to, the 32 bit version [~6 MB instead of 7] runs in win7 64 just fine [I just named it StylePixPro_32.exe]. Additional files are stored in C:\Users\ [UserName]\ AppData\ Roaming\ Hornil\ StylePixPro\ .Windows registry is used for 3 things -- file type associations, uninstall data, & the license key. FWIW I tried just running the software to avoid the file name/type associations, but it added most of those to the registry on 1st run anyway. The registration key is stored under HKCU [i,e, for Current User], so you need a permission level that lets you add the 2 values, & can either copy that key to additional users while you've got Regedit open or register after logging into those accounts.
StylePixPro wouldn't open raw image files, nor does it list them except in the registry [maybe it's planned for some later version?]. Most of the tools & controls you'd expect for a more capable image editor are there, though many aren't located in the traditional places, e,g, it took me a minute or three to find the equivalent to Select None, which is often part of a separate Selection menu up top. That's not why I didn't grade it on a par with PSP though...
The selection tools in StylePixPro are adequate, but what I would expect several years ago -- nowadays I look for some sort of automatic edge detection, where you just need to get close marking out the boundaries of your mask, & the software nudges your selection to the closest edge. Not having this feature isn't a deal breaker, but it can speed things up so it's something to look for. Second on the list is something I'd hope the devs have planned, & that's better levels controls. As a quick example, in PSP I opened a high contrast nighttime photo with lots of incandescent lights giving it the expected orange-yellowish tint -- using the 3 eyedroppers in the levels dialog I was able to get the levels right while getting rid of the color cast in seconds. StylePixPro doesn't have those eyedroppers, & while you might not always want or need them, in this case doing the same work without those eyedroppers took a while. 3rd is not having P/Shop plugins support...
Supporting P/Shop plugins is so common it's a de facto standard. The way that StylePixPro presents its filters I can understand why they went with their own format, but IMHO that's no reason not to present P/Shop plugins normally. No matter how good you are, there's no way to make up for the immense variety of plug-ins that have become available over the years.
Now none of that says you shouldn't use StylePixPro. You might find it easier than The GIMP, & it's certainly more capable than many [most?] free alternatives. And If Corel stuck to PSP's MSRP, the $50 price tag would be a fair price to pay. But since it doesn't, my suggestion would be that if you're going to spend somewhere around $50, wait for PSP to go on sale. [If you're very patient, Or in my case cheap, you might even wait for PSP to drop further -- I've seen X6 in the thirties, but since I've got X5, I'm holding out for another $10-15 discount.]