No worries
I've actually been in both situations.
The 05 Cooper S I bought "off the lot". The dealers in the Bay Area told me I could wait 5-7 months, or I could have the one I just test drove. At the time, it was close enough to what I wanted that I was happy enough to forego the wait. And I was certainly very happy with it. When it came time to get the new one, I wanted it to have exactly what I wanted (although even then it turned out that what I wanted when I first walked into the dealer wasn't -- after some discussion and further thinking -- what I really wanted!). And now I'm very happy again.
mmalc