Apple is still signing iOS 7.1.2 so you still have time to downgrade if iOS 8 is too buggy or sluggish for you. Info can be found here: http://www.idownloadblog.com/2014/09/20/how-to-downgrade-ios-8-to-ios-7-1-2/
If you have any questions on how to do it using voiceover, find me (esan100) on Zello at Blind iPhone or on Twitter Blind_iPhone.
Keep in mind that Apple is only signing iOS 7.1.2 and 8 so even though you see the other firmwares, you can't downgrade below 7.1.2. Apple usually stops signing older firmwares about 2 weeks after a new iOS is available so act fast if you want to downgrade. Hope this helps.