Today, I have a BK11, a 1259 and a 5055 (shorty Kabars, kraton handle, combo clip and combo tanto). On some days, a 1258 and/or a 5054 (plain blade versions of the 1259 and 5055) replaces one of the shorties. These 4 rotate based on which ones have been sharpened most recently.
I carry a BK11 so I always have a Becker for a Becker Scavenger Hunt pic, a bottle opener and a conversation starter - I've "sold" 20 to 30 BKs just from showing someone the 11 and talking about Beckers in general.
The 4 shorties are the kraton handled versions and have the black glass-filled plastic sheaths. The black handles/sheaths don't stand out as much against my black dress pants or my blue jeans as the brown stacked leather handles and brown leather sheaths do. I prefer the plastic sheaths over the black leather ones available (models 1254, 1255, 1256, 1257) as the plastic sheaths have 3 retention mechanisms (2 straps - 1 around the top of the handle and 1 down across the guard ambidextrously) and a couple of formed extrusions that snap over the guard.