Thanks.. good to be acknowledged by some who can move past preconceived notions and keep filling their cups. Those boxes are cheap compared to standalone ECU/TCU offerings when it comes to the ignition curve portion of the whole deal. Imagine a locked out ignition curve with buku advance that keeps retarding from that point onwards and the map sensor stops the rate of retard based on manifold vacuum levels/engine load. You'll never come close to the same curve with a traditional weighted advance curve and vac pot arrangement. If you're really interested I'd be willing to fire up the old laptop and post a picture of my 11.5 to 1 compression 383 Chevy's 54 degree base timing(until retarding from about 1,700 rpm onwards) and high speed retard layout. Pretty interesting what amount of advance can be plugged into a more serious combo solely for the purpose of increasing manifold vacuum. If you can move you'r distributor around and gain additional manifold vacuum?.. then there is more to be had in that combo. Just a simple matter of how hard you want to work and what you're willing to spend cash and timewise to get it.