This can be a sore point but we often find service techs are only as good as that particular person and how they feel that day! Before looking at changing the whole unit, I would make a pretty big effort to find the guy who actually wants to work on it! RV techs are not an area where there is too much regulation on what it takes to hang up the shingle, so some are much closer to knowing what and AC does than others. Did the guys who said replace it, really do any testing on the small parts that make the compressor run? If the easy answer is to replace it for the big bucks, I look for folks who actually do the testing first and that is not just simply listening to the story or trying to start the AC.
2015 Winnebago Vista 31KE on 2014 chassis
I am new to the site and actually dealing with an A/C issue myself. I thought I might toss out a couple of things that might be of some help. One of the problems we face is finding good service sources. Instead of burning up time calling around to the different companies in the area, see if there is a wholesale supplier for the particular area of expertise you are looking for. A Heating and Air equipment/supply company will likely know everyone in the business and what they do and whether they think outside the box, or not. They might also be able to offer some insight into the reliability of a particular contractor. I recall back in my working days in the electrical business, I frequently got referrals from suppliers and I really appreciated them. Hope this helps.
04 Horizon QD, 12 Ford Flex, Excalibar, Brakemaster, Winter Texan, RVin! since 1974
Norm, Donna & Tinker Kat 74 MGB-GT, 75 MGB, 01 Z3
Life is a Timed Event, you only get One Go Around!