I see your point. I know that car audio is a sickness for many, me included, and we often get buyers remorse by settling for less than we truly wanted. I'd definitely advise that before your buy a head unit, you find a local place and mess with them. You may find that the Sony has a terrible user interface, while a competitively priced Kenwood suits you much better.
You might as well buy what you want the first time, because settling for less will cost more in the end. IMO.
That's funny you say that, because I currently have a "competitively priced Kenwood".........and I hate it. The quality is good, the functionality is good, the looks are good, but the UI is absolute garbage.
I actually have the same belief as you too. I think it's most wise to buy what you really want the first time, but I also believe that you should first understand things realistically. I am also an audiophile (I got MECP certified just to do it. I don't work at a stereo shop or anything), but at the same time, I try to be realistic.
I choose to think about it this way: Would I like to have a 2013 Porche Cayenne Twin Turbo? Sure I would, but I'd rather spend half of that money on a Yukon, which can do everything the Cayenne can do, just as well.......Then, if the "Giddy Up" needs tending to, I've still got $40K to play with. The same thing goes for HU's as well. Figure out what SPECS you need, then get the cheapest HU that posesses the specs you desire.
Does that make any sense?