I notice they have regular boost gauges and boost/vacuum gauges and what is the point of a boost/vacuum gauge? What do you recommend getting?

 

well, so you can see vac and boost. pretty simple one lets you keep tabs on just boost, but the other allows for readings of both, which is important imo. I personally will be using a vac and boost gauge.

 

vaccum and boost is better. You can tell if you have a vaccum leak sometimes by checking the guage if you know where it normally sits at idle.

Two of my injectors bung rubber thingys were leaking and I didn't know it B/C #1 the car had an open DP ( VERY LOUD ) and #2 my boost/vaccum guage died of old age... After DP was done, we were like WTF ?? After driving it for about a week.