I am pretty hard on my phones due to my work environment and have been using OtterBox for about 5+ years now.... I am very pleased with how well they hold up.
I Just got my GS4 on Tuesday and my OtterBox Defender came in the mail that same day. My last three phones have been in Defender cases and come out like new when I removed them from the cases.... cases are completely thrashed though.
I couldn't be happier. Yes it's big and bulky... but from the past 5 years, The Defender Series has proven itself time and time again for me..Worth EVERY penny in my book.