I can certainly identify with your comments. I headed into the R134 deal about three years ago, starting with my old truck which I couldn't justify spending what appeared at that time to be "big bucks" for R12. I got guages, a 35 pound can of R134 and even upgraded my vacuum pump to gear up for changing over my older vehicles.
The truck didn't come out too bad, but I now have a leak I will have to trace, causing me to spend even more on a UV leak detector.
The 123 came out not bad, but the R134 expansion valve ended up being cheap crap and leaked. With everything on it in proper shape it still leaves much to be desired when it's 108.
Getting the interior making ice cubes in 2 minutes is certainly not part of my criteria, since my commute is over 90 miles one way. But it needs to make it to bearable temp in 10 minutes or so. R134 in my truck or my 123 car struggles to do that on a hot day.
An original R134 system is a different matter. The condensor is larger to compensate for the less efficient refrigerant. So these cars work okay. It's the retrofits that are usually a challenge.
If I could go backwards, I would have spent all that money on R12 instead of equipment and the like.