You should not need new servos unless that specific receiver calls for it. Advantages is most of the glitching and nearly ALL interference is gone. Range is increased and pretty much everything good. ONLY draw back I can see is cost. The 2.4s for the most part cost a good bit more. Just like anything there are a ton of ultra cheap RX/TX combo out there but like anything you get what you pay for. A $500 radio is always going to preform better than a $40 radio.
Oh wow yeah that is an old picture. I was going to be running in a huge sawdust pile and it was good to help keep some of the crud out when it came back down on the lid....