i haven't used motec so i can't say anything about it, but i recommend autronic because it's really simple to use and it has a base map... here are some of the features of the SM4
-Autotune (self tuning software). <---best feature in my opinion, gives a great base map
-Launch Control (two step rev limiter based on vehicle speed).
-Flatshift (change gears without clutch at WOT using standard gearbox).
-Antilag (keep turbocharger on boost during gear changes) with turbo cooldown function.
-Selectable ignition tables. Output tables can be based on any X and Y axis parmentier.
-Fuel and ignition tables have 32 rpm and 16 load site axis.
-Many correction tables for precision fuel & ignition adaption.
-Table axis values totally user selectable.
-Dedicated idle control with additional settings for better adaption to changing operating condition and a more stable idle.
-Dedicated Closed loop boost control, and other settings for stable boost pressures. Dedicated A/C compressor control.
-Dedicated twin cooling fan control.
-Dedicated NOS injection control, coordinates fuel & ignition.
-13 General purpose control modules for O/P control. (use for variable fuel pump, power steering, inlet manifold air valves, extra temperature control devices etc) 4 of these are capable of PID feedback control (typical application for PIDs are variable camshaft positioning or inlet manifold length).
-Mapping via manifold pressure, throttle position, manifold and throttle or manifold, throttle and exhaust backpressure.
the SM2 is really good too.
check out their website
http://www.autronic.com/