I had one issue with my alloy synapse BB30, when they shoved it in, there were AL. shavings peeled up and touching bearings. Took it apart, broke those shavings off, lubbed my spindle put it back together and never had a creak again until I put bike away wet. the spindle had corrosion it, wiped it off relubbed and was perfect! any bb and and bike will creak with dirty water dried leaving residue behind though. as in no different than dirty water down the seat tube and drying between your seatpost and seat tube.
I want a CAAD9 bb30 road frame for the purpose of using Beer components eccentric BB and I want a CAAD road SS with vertical drop outs. without all the seatpost tube FD bolt on ugly.

Then again I moved to hi-mod supersix DI2 disc brake for a road bike. A light weight AL framed SS road bike just seems redundant. So maybe I want a caad9 cyclocross singlespeed. as an additional bike < better choice super light TRP carbon cantilever, and not limited on tire choice.

Edit CAAD9 X SS like this
https://www.pedalroom.com/bike/2008-...aad-9-cx-24098