Hanka... a person asked for an advice, guess it could be a really interesting topic, especially if the experienced breeders could advice about how THEY choose studs for their litters. Our aim is one - benefit of the breed, isn't it?
Tikaani, maybe only theoretically - here are nice articles, that you, I guess, already know:
http://www.britishdogbreeders.co.uk/
Also i found some simple advices from a known scotch terrier breeder in LT (
www.terjerai.lt) Of course, it is just the base, but these are some important points in choosing a stud dog for a beginer breeder:
- the minuses of the male and female can not be the same;
- you should chek for some really good common ancestors in both dogs' pedeigrees;
- the male should not be worse than a female.

sounds simple but it is not

She also made comments on this, but it is in Lithuanian terrier forum, if you think this info could be interesting, I can translate it.