The bad things you heard were from people too lazy or adverse to change to bother getting used to / customizing a new UI. Windows 8 is a fabulous OS - it's windows 7 with a way better copy manager, task manager, search function, and all while being lighter.
You just have to take a few minutes getting rid of metro apps - don't ever use them or the windows store. Then get used to using the windows button on your keyboard rather than a start button (which is faster anyways) and you're all set.
In addition, if you buy windows 7 OEM (which is now 4 years old), you have a pointless RAM cap on it unless you buy more expensive versions (and no, "ultimate" is not better - you don't need any of the features it has.), and the OS is bound to your motherboard. If you buy windows 8, you can buy the home edition, as there isn't a money-grab limit on your RAM, AND when you build a new computer in the future, you can just de-licence the old computer and transfer the licence to the new one.