I only ever knew 4th edition. What's the difference? Worth to swap?
The differences are whole lot of flavor. 4E is easier to play and to make characters and they ramped the power down especially those of mages and shamans. And they homogenized them so badly imo that they should just be the same class now.
The thing is in there quest to make the game more modern and user friendly and to appeal to the 20 somethings they took a great deal of the flavor out of the system.
For example they made the tech go wireless because the game was made in 1980s so they thought kids wouldn't get a non wireless world. To me it made no sense at all that a world that was so vulnerable to cyber hackers would make it easier to hack the system.
Then they made it less deadly for hermetic mages to summon elementals. Now elementals are just as tame as spirits. The idea was elementals were very powerful and yes that was true but the mage spent a fortune and risked death every time they summoned one to bind it services.
Those are just a few of my beefs. I don't have access to any books right now so I can't look through them and see what else there is.
I know that I took a character from 1 to 3 edition and yes it required some tweaks but the character was still basically the same trying to convert to 4 was impossible. To make it playable I would have had to gut the character.
I have been teased by my gaming friends that I have an issue with the number 4 because I feel the same way about 4E DnD.
I think if you are happy with the way game plays and you enjoy the world why swap unless you get a chance to play with people who like the older versions.
I do think it is worth looking at the older editions if you can to see how the game was done if you are interested.
My son loves 4E Shadowrun but hated the older versions so I know a lot of people do enjoy it.
I really dislike whole scale changes to a game at that point I wonder why didn't you just make a whole new game and call it something else. One of the litmus test for me is converting characters if you can do it fairly easily from one edition to another then we are good but if it is impossible then I get irritated.