Hi Mike,
IMO, there is a difference between the questions, "What do I need to come out and shoot my first few matches?" vs. "Now I want to 'get serious' about 3Gun-- what do I buy?"
The answer to the first IS that it essentially doesn't matter. Here's that segment of the reply I send back to CO guys asking for 3Gun info--
Once a guy has shot 3-4 matches, he will be acquianted with some of the shooters, and can kind of see what people are using. He will discover BE.com. He can get clarification, reasons, and good advice.
The reason we always tell people to "not buy stuff" right away is so they don't end up with that "wrong stuff", you talked about.
The most important thing is to get out there, not focus on gear.