You're very right, and that's fantastic advice.Just start buying guns you want to try out and if you don't like one for some reason you can always sell it and move on to the next one.
If you buy a gun right, you can sell it without losing any, or very little money.
I doubt that very many people get their "perfect" gun on the first try. Even if it is "perfect" at the time, things and people's preferences change.
Have fun trying out as many as you can.