Reply to SL2 vs SL3

Hi guys. Been djing now for almost 11 years and made the progression from vinyl to cd (reluctantly) and I am now on the brink of buying my first dvs. Can anyone give me some pointers as to the differences between SL2 & SL3 apart from the option to have a 3rd deck on SL3? I am also going to pick a pair of Novation Dicers to go along with this set up. I'm just struggling to justify the