Hmm. I'd say the headset and pedals on the Kilo TT are cheap garbage, whereas they are decent on the PB. Other components like the chainring and seatpost are nicer as well. The aluminum track nuts are easily and inexpensively replaceable with steel ones. Then there is the much nicer dropouts and seat binder lug on the PB, which can't be upgraded on the Kilo TT. Finally, there's the simple fact that it's a nice lugged frame with a threaded headset and quill stem that so many people would prefer. No need to convert a Kilo TT to threaded. As to the low BB on the PB, that won't be an issue for those riding it as a SS, and it comes standard with both a freewheel and fixed cog, whereas the Kilo is supplied fixed only.