I have 3 borders and all are different.
2 are from a pedigree show line and the third my youngest is from a working farm and boy can you tell the difference.
The oldest is now 8 and she was my first dog since i had left home,i had always wanted a border but my parents always had labs and said no! me and my oh were living in a rented house whilst looking for a smallholding he had 4 very young children 3,5,7 and 9 that stayed with us every weekend,we found a local ish breeder who was well known and recommended for her help and advice,when we first went to see the breeder she had no puppies at that time but had some due soon we had to wait a month before they were born,we went to see the pups at 2 weeks old and choose ours and then we went back every couple of weeks to see her until we brought her home,cassie lived in the house for the first year until we moved to our smallholding but there were rules she was only aloud in the kitchen and had a cage witch was her safe place if she wanted to be on her own,the children new never to go in to the cage to speak to her they were aloud to call her out and if she wanted to come out then fine but if she didnt then leave her alone,they were never aloud to feed her or go near her whilst she was having her dinner.
Once we moved cassie would not come in the house and has lived outdoors every since, when she had her pups i made her come in as it was winter every time the front door opened she jumped out the pen and shot out the front door,she just found it to hot inside,i kept 1 of the pups her daughter who is now 5,spangles is more like her dad completely different to her mum.
Then the 3rd well she was from a working farm and is a complete nutter so very different to the other 2,she has the working gene which showed up very early on,will herd anything that moves, geese , chickens,ducks she couldn't get to the sheep but as she got older now shes 18 months
she easily jumps any fence to get in with the sheep seen her clear 5ft no probs, latest trick is jumping through the 5 bar gate, as its there i now take her for sheep dog training once a fortnight and in August i will be getting some of the sheep we have been training with so i can do a bit each day with her to keep her stimulated.
The other 2 have no desire what so ever to herd luckily.
So what i was trying to say in my long winded post was if i was you i would think about a show line not guaranteed but you might find a pup that is less of a handful like mine and is less likely to herd.