Buyers Guide for Mityvac vacuum pumps
 

No, this thread's not a joke.

I recently did a vac hose job and needed a vacuum pump kit. So I bought the model stocked by the local harbor freight store. Shoulda bought the better model (Silverline Plus).
1) Made of metal in USA instead of plastic, and operates more smoothly.
2) Switches from pressure to vacuum by flipping a switch - the plastic version needs to switch hose to another nipple and they're not marked
3) Plastic model doesn't show pressure on the dial - need to buy a separate pressure gauge and tee it in when applying pressure. Total PITA. By the time I bought the extra pressure gauge the whole thing cost more than the better kit and I wasted a lot of time messing around with the hose arrangement to make it work.
4) Silverline plus goes to 30psi of pressure, plastic one only 10psi (the FD has a couple tests which require 12psi IIRC)

All said, the plastic version sells for about $45, and the Silverline Plus was $65 shipped from an Ebay store place. Had I known all this I would have ordered it and stretched out my vac hose job a few more days for the better tool. When I read the product info online it just looked the same as the plastic one but made of metal - in reality there are big differences.

Oh, if anyone wants the plastic one it's for sale :) (Actually, it would be fine for a non-turbo car with only occasional pressure tests).