From what i've gathered so far:
# 93440806 is M.I.T.----made in taiwan.
# 88961867 is made in usa and has an admission price of $299. To me, this is not a problem if it is of high quality and it seems to be high quality. GM included it with the aniversary 427 engine and i think that is saying alot. Also, i read it has an rev limiter built in.
# 141-682 , 681 and 683, i'm queasy of anything made by proform.
i've heard good things about pertronix. i'm not sure about msd---i've heard good and not so good.....