I like the idea of a small dog with a big attitude to life
Then you'll not go far wrong - Ted, our border, is a top little chap.
A quick read up on the breed will tell you they were brought in to being to join the hunt - able to run with the horses for the day, digging out foxes that had gone to ground - hence their stamina, strength and (if pushed) their ability to punch well beyond their weight - nowt to do with small dog syndrome at all
Ted does need stripping (loose hair pulled out, find someone who does know what they're doing), don't have them clipped, ruins their coat.
They are kind of catlike though - your best mate when they want something / want to cuddle up. Not your mate at all when they get a scent they just have to follow. Ted is rarely off the lead yet - though i'd say that is 99% down to us, not him, he needs more focused training in that area