Should I exhange my s4 if I experience any lag? I have lag on the keyboard, especially on the browser that takes about a second for my letters to pop up when im typing or sometimes it doesnt pop up. Also occasional lag when changing apps. I understand there are somw things I can turnoff, disable, etc i want my phonw to be lag free nonetheless as some people have reported about mot expeeiencing any lag. Is it a good enough reason to exchange?