Thanks for the kind words.
Those Yellow Jacket gauges work very well, but I cannot objectively analyze their longevity as I bought them some 5 years ago and they sat unused, waiting for the a/c to fail. Once it did, I was motivated to learn all about a/c work. Thus they have been used only a handful of times.
Are they accurate? Well, the instructions for the venturi vacuum device I illustrate state that it should generate 29" of vacuum, which is exactly what my gauge shows. Plus, the pressure readings vs. weight of refrigerant in the system correlate well, so that's some comfort they are reasonably accurate. And, as I know to my cost, they instantly show a leak. (My condenser blew and the gauges immediately confirmed a vacuum leak - I couldn't get anywhere near 29 inches of vacuum).
I can't find this brand sold as a set on the web, but I would think any of the sets sold by ackits.com would be a good alternative - the company specializes in a/c. The leak detection kit they sell (see my web site) is very useful, too. For occasional use, I would go with the least expensive set. Don't trust their web site if you need them fast - call and check they have your item in stock first. I waited an inordinate length of time for the Mastercool a/c book, as they took my money without the item in stock. The book is exceptionally useful, despite the focus on US cars. Most of the a/c components in my W126 cars seem US made, and many of the fittings are non-metric.
By way of reference, I seem to recall I paid under $100 for the yellow Jacket gauges - they are calibrated for R12, R134a, R22 and some other R.
Don't forget to add beer to your shopping list. A dog helps too when you need a break to relieve frustration.