R56 Cooper S - subtle hunting when cold?

[jam3zs]

Hi Guys,

I'm currently looking to buy an R56 Cooper S.
I went to look at one yesterday, 08 plate, 46k on the clock, FSH etc, and it was pretty much perfect, the only thing that concerned me slightly is that when it was first started up, the revs seemed to "bounce" slightly on the 1k mark.
It wasn't that bad and it wasn't like it was struggling to not stall or anything.

Any ideas what this could be?

Thanks in advance!

James