Jake used Mallory unilite #4554101, mechanical advance for years before quality control issues began to surface in 2007. If you plumbed for Vac advance, why not take advantage of it.
You might email
John@aircooled.net, he sells the Mallory Unilites in Vac advance and Mech advance configs. He usually does a quality check on items he sells, maybe he has more info about what would be best for you.
Also, read this,,,,,, It's a Mallory Unilite quality control thread over @ The Samba.
http://www.thesamba.com/vw/forum/vie...hlight=mallory