This was my experience with a pertronix Billet Flamethrower distributor. It's long,sorry.
I've installed Pertronix units in a couple of points distributors and been happy with them so I decided to buy a Pertronix distributor for my 351 Ranger. It's shiny billet which didn't appeal to me but it had bearings instead of bushings on the shaft and was very simple to wire. The problem is the centrifugal advance mechanism. It looks like a GM unit and the springs and weights are under the cap and easier to access than a Ford distributor. But they don't work. Centrifugal advance should come in smoothly and in a linear manner as the RPM's increase and drop back to base timing instantly when the engine returns to idle. My distributor didn't advance at all until it had been held at about 2000 RPM for at least 8 seconds and didn't return to base timing until it idled for 14 seconds. If I put in lighter springs it would advance at 1500-also after 8 seconds- and only dropped back when the engine was shut off. I called Pertronix in the summer and described what it was doing, at first I was told it couldn't do that, then he suggested I see if Summit would exchange it and call him for a replacement if they wouldn't. Summit replaced it without question even though I bought it 14 months prior. The replacement worked exactly the same so I called Pertronix again and arranged to send it for testing after I parked the truck in November. It cost $35 to send it and I just got it back with a note:"tested good" , no details, no comment about the advance, no date or ID of the person who "tested" it. I assume they plugged it in, spun it up and it threw sparks, and put it back in the box.
If I had a good 351 distributor with a roller cam compatible gear I might put a Pertronix unit in it because the Ford advance mechanism works. I didn't.
This distributor is a shiny turd and would be perfect on a Chevy small block with billet pulleys and an Edelbrock carb. The folks at car shows who are impressed by bling would love it.