Hellooo....I had three subject interviews in total (as I was pooled)
The first two, one was biology and one chemistry, biology was ok, questions were interesting and generally not too bad. Chemistry one was pretty awful...I just had a mental block and couldn't think at all.
Then I was pooled and had one (fairly long) interview that covered biology and chemistry again. I was sent an article for this one which we spoke a little about (but not much!) and was interesting, a few things that I'd mentioned I was interested in most and scientific questions stemming from that. Then it went into chemistry, bond angles, ions, and then a mathematical rates kinda thing which wasn't as bad as I thought it would be.