I would agree about all that’s been said about the Megajolt! I ran one for a few thousand miles on my old Westfield, never missed a beat. The chap that bought the car did 10,000 further miles with it and he told me it was faultless! It also improved my fuel consumption somewhat as well!
As Bob says, you can run the system in limp home mode just using the EDIS system.
As for the maps, I sent my map to quite a few people who never bothered to have their cars on the rolling road; no one reported any issues, even with one guy running a 160BHP crossflow on the map! His stance was that where it was important, eg the higher rpm and load, (in terms of doing any damage to the engine) the advance was all in at that stage anyway!
I still have the map if you need it, plus there is some info on my web site below.
1997 HPC