I am a firm believer that your opinion of a game is in response to the exact tables that you have played over the years. The newer the machine (of the same title), the more similar one plays to to another.
So, these early solid state games have a MUCH wider gap of how one title of the same name plays to the next. I think that is one reason people seem to have such strong opinions of older machines. The older the machine, the wider the opinion gap.
Possibly it would only take one single experience on a Star Gazer or Quicksilver to change my mind. I have played two examples of each for a very extended time (many multiplayer games for hours) to learn to detailed rules of each table. I have decided that neither are worth owning. I suppose I could change my mind but that is probably just as likely as someone who does not like Fathom, playing a different example of it and changing their mind on the spot, erasing all the negative playing experiences in the past 15 years.
Truth be told, my favorite Bally game is my Mr/MS Pac-man. Every other single Mr/Ms I have ever played was absolute crap. Lamps/switches not working, flippers not aligned, ect. Yeah, I know. Flame away.
Back on topic, I don't think you could buy a decent Seawitch for less than 2500 these days. The other two are basically impossible to price since it's a sellers market on those 2 titles. Could you buy one for 3K... maybe a beater. 5K gives you a better chance at them but you can't buy one for 5K if you can't find one for sale. A few have been "built" from parts or populated PF's. That's seems to be the way to go if you are on a budget.