I'd check the lines of any border - I'd want to meet lot of siblings, aunts, uncles, cousins - as I have come across quite a few who are really arsey. They can be fab, but I've come across too many who are dog aggressive or just a bit too snarky.
Borders are great little dogs - healthy, hardy and will go for miles. However they are terriers so they do need a fair amount of exercise and stimulation to keep them occupied and to stop them digging up your garden!
Socialisation is a must - I've seen a few recently who are quite reactive towards other dogs - pulling and barking on the lead. I'm not sure whether they just want to play or whether they'd be aggressive if given the chance but as with all dogs early socialisation is vital
We are seriously thinking of getting a Border Terrier puppy. We very sadly lost our wonderful Cavalier King Charles 3 months ago aged just 8 and are very aware of the many horrible health issues which affect this breed. Can anyone offer pros and cons on Border Terriers? Many thanks.