cogadh: The problems I have seen with DirectInput are simply on the hardware side, not the software side. If you have an old DirectInput gamepad, the OS might not even detect it properly, but if it is detected, then old DirectInput games will (usually) have no problems, but you can pretty much forget about playing anything new. If you have a Xinput gamepad (which is virtually guaranteed to work on Win 10), it seems to still work fine with DirectInput games and of course all new games. I don't even have to use the DirectInput switch on my gamepad with old games anymore (the F710 is both DirectInput and Xinput via a physical switch). With Win 7, I had huge problems getting DirectInput games to work properly and often had to resort to third party apps like Xpadder just to get basic functionality. 10 seems to have resolved that (so far). Basically, the only scenario where you are going to run into problems is if you are still using very old gamepad hardware that you probably should have replaced a long time ago. Frankly, whether or not you like DirectInput is meaningless. Xinput is the current standard and has been for almost a decade now. No one really makes games with DirectInput support anymore.
timppu: It seems to me you are mixing up things. Old games which use DirectInput, don't magically turn into XInput games just because you run them in Windows 10.
You said you had to use XPadder on Windows 7 with your F710 pad to get old DirectInput games to work. I have no such issues in Windows 7 with Logitech F310,
when using it in DirectInput mode. If I insist running the gamepad in XInput mode, then it may have some issues with older DirectInput games, like controls being located in the wrong buttons, the D-pad not always working, and/or issues with some analog axis. Those issues are pretty much expected.
I guess the main question is, how does your F710 work in Windows 10, if you put it into DirectInput mode? Does it work with old DirectInput games, or not? Is this somehow different from how it worked in Windows 7?
Your message is the first time I hear that Microsoft would have dropped DirectInput support from Windows 10. Yes that would certainly be a big drawback to me, as it would mean I couldn't e.g. use my (DirectInput) flightsticks and such with Wing Commander Prophecy, Freespace games etc.
I'm not mixing things up, that's simply how it seems to work on Win 10. I'm not saying games are magically converted to Xinput, but the OS is obviously handling the input differently enough from 7 that many old games "just work" (every one I've tried so far).
On Win 7, whether or not I flipped the switch, many older games had issues detecting there was even a controller connected and I would end up using Xpadder (or something similar, I've used many alternatives) to map keyboard/mouse functions outside the game. By all rights, if the gamepad was in DirectInput mode, it should have worked exactly as it always had back in the XP and even 98 days, but that wasn't always the case. Oddly enough, the older the game, the more likely it was to actually work correctly. Mid-2000's games were really hit or miss.
Honestly, I have no idea how the F710 will work in DirectInput mode on 10, I haven't run into a situation where I have needed to try it (yet).
MS hasn't dropped DirectInput from Win 10, but it is only there for legacy purposes. I think the problem with older devices is more about drivers for some DirectInput devices not being supported by the OS, or devices not being supported by the generic drivers that MS supplies, rather than a change to DirectInput itself. I actually keep a Logitech Wingman around for my flight games and that surprisingly works perfectly on 10 (it is very much not a Xinput device), but then this Wingman has surprised me every time I've upgraded Windows (had it since probably 98). Anybody considering a 10 upgrade really needs to look into driver support before trying anything. I had a laptop that lost its touchpad after a 10 "upgrade" thanks to messed up drivers, and it is just a basic Synaptics device, like laptops have been using for well over a decade now. I eventually got a driver that works, but I still can't get the edge scroll to work.