how is this car going to act

 

Mini spools are designed for dirt track racing or off road use where tire slip is normal. On the street with both axles locked, the tires will turn the same speed as you go around a corner. Normally with differential action, the outside tire will turn faster than the inside one because it has a longer path to take.

For street driving, this means you tires will probably wear quicker due to the scrubbing across the pavement, there may be jerking when going around corners and in poor driving conditions like rain or snow, handling may be an issue. If the tires grab while one is trying to go faster than the other, there's a chance you could break an axle.

You're much better off installing a good posi for street or street/strip use although many people have used mini spool on the street.

 

There are no positives here, only problems. Even at the drags tire run out has to be perfect. I don't like them or recommend them. A good posi will do everything you need.