Hi James
Sorry it's a little late....
I just got back in from JKM where I had mine Revo'ed this Morning.
That dodgy ness has been entirely removed from mine by the Map.
I spoke to Jim who installed it and he said it's the EGR that causes
Your issue so either get a Revo remap which will give you a very
useful power increase and take away the EGR shunt/Stutter or perhaps
Take your EGR off and give it a clean which may
help.