i just wired up an SM4 into an MZ21 7M-GTE last week. TO be honest i think it's about the best value for money aftermarket ECU available now, thanks to the myryad of features and configurable inputs/outputs thrown into the SM4.... along with all the other features that are always compared (ie, processors, ignition drivers, etc etc)
Price - well i can't really say what the retail is on them, cos i dont know. I just know i will be buying at least one for myself and my 18R-GTE (project).
R-Jay, was it S.A.S. that you visited per chance?? If so, the MZ21 is still there as they were unable to tune it last week (no time) and wont be able to this week either. However a brief 30 min tune, 3/4 rpm, and 0.8bar boost laid down a humble 243kW at the wheels though....
As for knock control - well it will aparently be added to the software's programability in the future..... but you know what... WHO REALLY WANTS KNOCK CONTROL???? I know i sure dont! Knock control is only there for tuners who can't do their job properly and tune OUT the knock, if it exists.
Currently, the SM4 can connect to a wideband sensor for tuning functions, and the "add-on" AUTOTUNE function!!
as for this TEC3 thing....... i think there are enough references to the following from the Simpsons to convey my point accurately!!