DM and I both had SCWT for many years a few decades ago. Here are a few generalities:
1)Although "soft" in temperment compared to most terriers, they ARE still terriers. This will show itself in barking, digging, sometimes dog aggressiveness, being territorial, some are good with children/strangers, some are not, etc. All helpful for their original "jobs" of guarding the homestead, killing critters that were pests, etc, but not always good for a family pet. If you have a child, I would work with a reputable breeder who would place a puppy with you who has a "softer" temperment (often a male, middle of the pack in terms of dominance). Puppy classes and then regular obedience classes are a must.
2)The coat MUST be kept nice by a groomer on a regular basis, or you'll have a matted mess. It is not "hair" like some of the toy breeds have that claim to be hypoallergenic. Some have a tendency towards ear/eye infections, if the hair is not kept clean and plucked from these areas.
3)Buying one from a reputable breeder is an absolute MUST. Please don't get one from a backyard breeder, or, god forbid, a puppy mill. Yes, they'll ask you a lot of questions, and you may have to wait, but it will be worth it to get a pup of sound mind and body.
4)They are a fairly healthy breed, with few genetic issues, and are very long lived. This means you need to think about what happens when your daughter goes off to college and leaves you with the geriatric dog who needs pills, special care, to go potty more often, etc. My DM has a female that is 14, and just starting to really slow down. She's going deaf and blind, is arthritic, but has nothing wrong with her that's going to kill her, so may live a few more years needing lots of care.
Having said all that, we dearly loved each and every one we owned, despite their idiosyncracies.
You also might want to think about an Airdale. They are slightly larger, but have the terrier coat that doesn't tend to affect allergy sufferers. Out of all the terrier breeds, Airdales are kind of like a Lab in a terrier body: loving, playful, silly, just big galoots.
Good luck!
Terri