Should probably look through reddit. Lots of resources of right.

http://www.reddit.com/r/keyboards

e.g. Keypress force.

Red (45 centiNewtons, 60 cN) Brown (45 cN, 60cN, tactile) Blue (50 cN, 65 cN, click/tactile) Black (60 cN, 80 cN) Clear (65 cN, ?) Green (80 cN, 105 cN, tactile)

Most people seem to like Blue and Brown. Blue sounds clicky.