I will EDC a comfortable fixed blade up to 4". Currently my favorites are:
--Original '70's Tekna Ocean Edge dive knife--a classic; always my favorite urban or watersport fixed EDC since I was a pup. Maintenance-free and a terrific lock-in sheath for odd carry placements. Also a perfect handle for intricate leather or para-wrap if desired...did mine in leather...also parawrapped the open part of the sheath.
--Original DPx HEST fixed blade by Rowen--just a blast of a knife. Now re-released by DPx; tough, super-handy pry bar on the handle saves the tip from prying stresses/breakage. Good for knockaround carry anywhere.
--TOPS/Buck CSAR Liason--good small knife; the best, lightest, inconspicuous small-knife horizontal carry package (with the addition of two cable ties through the Kydex sheath grommets) I've ever come across. Also--pocketable as is.
--BK-11 san mai--just because of what it is. Another classic.The factory sheath at the time sucked though.
--Gryphon M-10 with boltaron sheath--simply a great Terzuola-design knife and VERY comfortable, solid carry package anywhere on the belt. Probably the most secure and comfortable-in-any-grip handle of any of my knives, period. Tipped to me last year by a member's post here.
Couple of runners up/on deck:
--Bradford Guardian 3
--Hinderer Flashpoint
Another vote here for the fact that a good sheath is the key.