I have used both large HEI and Tom's mini HEI. The truck I used the large HEI on had a fined aluminum side cover. The large HEI would not clear the fins without grinding them down.
The mini HEI works fine and looks okay but it does not look stock. For one it uses a completely different looking vacuum advance, and the plug wires do not connect or look the same. Nit picking I know, but in most cases I like the stock look.
When I questioned the reliability of China parts for HEI's I was weighing those against the reliability of the Pertronix. Both can have problems. I personally have not seen a HEI or a Pertronix fail. I have seen the rotor burn through grounding the spark on HEI's but that is all.
I really think the problem with most Pertronix failures is from incorrect installation. One really needs to dig deep and understand wiring and resistance to get the correct info and installation.
