they are all a much of a much really but you leanr one and then stick with it i guess...megasquirt is more open forum than omex or other products which are supported by a single manufacturer...it means you really have no one to blame if the thing goes wrong...
I like megasquirt because I have dealt with one of the developers over the years...
I like megasquirt because I have dealt with one of the developers over the years...