I'm looking for input on witch gauges I should get. I have two more semesters of college left and have been slowly buying tools, gauges are one of the last tools ill need. I do have a pair of yellow jacket for R-22 but need another for R-410a. I've been thinking about buying a set of Hilmor Electronic Gauge - Vacuum, Hoses. Witch price at $690.00 has anyone used these or have any suggestions?