Folders: I like Spyderco the best for performance and user friendliness (specific models in particular for the latter, Tenacious and Resilience particularly, and always modded to my liking of course). I do own others, but other than Cold Steel, I don't really go out of my way for other brands of knives, and if I get them it is by accident/happenstance.
Fixed blades: Well aside from a cheap set of kitchen knives I own (I may eventually replace with something I made if I can ever justify the cost), I'm always carrying a necker and a fixed blade that I have made. Been carrying the same necker for most of the year, and have moved into a new large EDC slicer, which I am not ready to show off just yet. But I have a DEK1 coming as a trade soon, which I will use to hopefully gain some insight and inspiration as I progress in my craftsmanship journey.