BG 3.0 vs. 4.0- does it really matter??

sarbear2

So we are trying to build up our cloth diaper stockpile. We are newbies I see the bum genius 3.0 (with the hook/loop closure) I can get on sale. Is there a big difference between the 3.0 and 4.0? If so, what are they??

 

Thanks!