CY is a touch stiffer and more repulsive and slower. BS frames are one of the fastest sharpest frames ever. If you want a solid all arounder bs12 is ur go. If you want a bit more repulsion go with AS-CY. If you want super accessible and friendly racket with a large sweet spot then 90F, it'd also headheavyish
Make sure to get your equipment from official providers, such as us, and try to avoid ebay as many of the rackets there are counterfeit. Really tough to verify racket authenticity online until you have it, and even then hard sometimes unless you hold up next to an authentic one and can see the changes in cosmetic. In the handle there should be a sticker with a serial number or sometimes it's etched into the shaft. Yonex also has a hard to replicate holographic sticker on the cone above the handle, which counterfeiters usually can't make look right. Hope that helps!