The click sound that both of the ones I mentioned are pretty close in sound (SI more than monterey blues), and also are close in actuation point. I've even had SI near blues and when someone else types on both, it's actually a contest to determine which is which by sound alone (granted, that was when both were new to me, so I may be able to do it now). They also both do not have hysteresis, which does, in fact, make them objectively better. This is only irrelevant if hysteresis matters not at all.
Space invaders also have more stability, because the entire visible switch is also the slider. There is no way to replicate that without doing a similar thing.
I will say that there is alot of room for opinion, preferring linear over others or what have you, but when there are objectively measurable differences, they can absolutely be compared in those terms. Given your sig, it also looks possible like you've only tried blues for clicky. Even if it were alps vs blues I'd agree that's mostly preference, other than still having hysteresis issues.
But hey, I guess I shouldn't complain too much, because it makes it easier for me to find non-cherry things.
Edit: @tricheboars
A hipster, lol. Just so you know there is alot of variation in vintage alps. I have/killed-for-click-leaves a white alps board that is amazingly stiff and was useless for virtually everything, not sure what they did to it but it was not particularly likable. So you could have easily tried something randomly bad. Now that those same click leaves are in something else which did not have the same stiffness problems, they are much better (though I haven't put caps back on yet - that's the last step). There also isn't much 'journey' in just buying stuff on ebay, for example my monterey blues - was I lucky when I got it? Absolutely, but that didn't color anything about it. I haven't even done anything to it.