That "bump" on the browns? That's what lets you know exactly where the actuation point is. Linear switches don't have that. When you are touch-typing fast or if you are hitting the keys hard enough to bottom out, then browns feel more or less exactly like reds. The new switches do feel a bit "crunchy", but they smooth out after you've put a few hours in. And blues are a super-fun clickity-clack experience. I'd love to try clears or greens.
I've purchased a single white switch recently and put in a blue spring and a red spring. the white switch with a blue spring and red spring feel identical to the brown. But with the original spring, it's way stiffer.
I don't like the browns, which is why i wanted to try the white switch to see if I can get the Blue feel without the click, but turns out that's not possible.
Blue has a special feel because the inner click mechanism slides across the base stem, and thus the activation leaf is not in contact with the base stem during the entire keystroke, which makes blue the least friction-y feeling switch
On the Red, Black, and Brown, the stem grinds against the metal leaf,