Ok

apparently owning a Canon 40D makes me a photo expert in my family (if only they knew)

Anyway, christmas is coming and my sister wants to buy her boyfriend a lens for his Sony DLSR, Not sure of the model, but will be a mid-low range I expect. She has asked for some advice...

He has not got a good zoom lens, so I was looking for a good recommendation for a 70-200 or equivalent for around £200

Any suggestions?

Well in the used lens world for the Sony/Minolta A-mount the 70-210/4 lens has a mystical status. That would be my first recommendation. Usually refered to as the "beercan" due to it's size.

Thanks for that - I'll send her a few ebay links I found for them in the UK

Yep, Beercan is the way to go.

But the Minolta 100-200 f4.5 is dirt cheap and surprisingly good (it's also very small)

Avoid the current 75-300