Okay, my experience so far:
the old blue alps (without the logo on the top) feel exactly the same as the very first generation white alps (without a logo on top too).
However, then there is the newer types of white ALPS that is also used in late Focus 2001 boards that do not feel nearly as smooth. I think this is what Sandy meant when he said "once you use original complicated ALPS you will know".
I dunno what else to write here. As with every aLpS related topic there is not really one solution to it. ch_123 should be receiving the blue switch board I sent him sometime this week and hopefully will like them as much as I did.
One thing is for sure: blue alps are good stuff.
Yes, as I have both these switches. The blue with no logo, and the focus white complicated with alps logos on top, not to be confused with even later focus boards that used simplified switches where there's a huge difference. I can tell there is a difference, between real blue and real white, but it's very very subtle. The blue alps switches seem to be a little stiffer in general imo. But this can also be effected by the caps. If there is a difference it's far less than what type of cap the switch has, or how the switch is mounted, that's for sure, and nowhere near the difference between fake and real.
Typically the original blue alps switches come with a cap that has a more rubbery stem and underside than later complicated alps switches which may be constructed entirely different, usually with harder plastic, which may account for a large difference in impression between one or the other.
It would be interesting to run a force test like they have on that one Japanese page with force graphs, on the blue and white real's and see what the exact microscopic difference is.