For audio books I have always used Ambling Book Player. It has skip fwd/back settings and has played everything I have thrown at it. Wow, I just looked at the download page and it hasn't been updated since 2011, but it works so well I have never thought about replacing it. After seeing some of the screenshots of the ones you all are using I may upgrade to one of those merely for aesthetic reasons!
https://play.google.com/store/apps/d....bookplayerpro