Well put it this way, Windows 7 has been around for quite some time now and the software and drivers available have had numerous revisions so are relatively bug free.
Windows 8.1 doesn't offer anything more than 7 other than it's immaturity and that can lead to issues until they get fixed. Ok it's got a quite a boost in security but can't you get that from a good firewall?
No gaming advantage, in fact, the modding community have found that the Direct X application used in 8.1 causes a headache that just isn't there in Windows 7 so it's a very significant experience in that regard.
I bought Windows 8 when it was released and used it up until a month ago, also upgrading to 8.1 as soon as that came out. Metro isn't an issue to me, looked lovely but I just didn't use it and that didn't hinder my experience and I used it exactly as I used Windows 7. No more and no less! However I had a few issues with the generic+proprietary drivers using LAN and bluetooth, poor implementation of the audio mix adjustments for specific applications but the biggest hurdle had to be my NVidia driver crashes. I couldn't install a driver update without it crashing before completion, even after two fresh reinstalls of 8.1 it still reappeared. There aren't huge issues that will appear on every system but it's another example of issues found on an immature OS.
I decided to roll back to Windows 7 and it's all smooth, all fully supported, all ironed out and stable. Windows 7 is still the only OS I've been able run for several years without an issue that was large enough to require a full Windows reinstall. That alone is incredible!