I have the Tein Flex Z on my car and for the money, I don't think you'll find a better street coilover. They're not meant for full on track abuse but light track work (lapping days and HPDE) they are perfectly acceptable. If your car is seeing more track abuse but you still want a comfortable coilover at a reasonable price, CSG Tein Flex A is the choice, or the RCE SS1.
Obviously there are more high quality choices with a higher budget, but in the range that you're looking with BC, there are only a few options that are actually engineered properly for our specific vehicles.
The car handles well with great balance, and the ride comfort is top notch. They’re quiet like the factory suspension with no weird clunks or noises even with the pillowball mounts. Due to the higher spring rate than factory, you do feel a bit more of the dots in the road (asphalt joints, etc) but it never upsets the car or feels jarring - it’s actually nice to have that extra road feel through the steering wheel. However, over larger shocks and bumps I actually feel the Teins absorb them better than stock at 7 clicks from full stiff, while still cornering flatter. Keep in mind the OEM 2017 suspension rides pretty well as it is, leagues ahead of my girlfriend’s 2015 WRX.
For longer trips or city driving with rough roads I leave it at 7 clicks - for sporty driving, 5 clicks from full stiff is perfect.
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CSG Mike has in depth impressions on them as well, here:
https://www.ft86club.com/forums/showthread.php?t=81829