Greens and Clears are hard to compare with each other. It'd be much more accurate to compare Blues with Greens and Browns with Clears. However, where the Greens just have a stiffer spring than Blues (stems are identical but just different colors), the Clears have a stiffer spring than Browns AND a different stem where the tactile bump is much more pronounced which leads to a much more longer and tactile response.
I find that the Clears are hands down the best and easiest switch to not bottom out on because of the very long and pronounced tactility. Because you won't be bottoming out on the switch and lifting off after the tactile bump, I find that typing on the Clears is a lighter experience than Greens. I believe the Greens design makes it so that it's much more satisfying to bottom out on because it's harder to control your press with the stiffer springs and much more shorter tactility. I don't really think that one is better than the other but just what one prefers more in their switch. They are my 2 favorite stock Cherry switches and you can't really go wrong with either.
However, there is the issue where many have experienced quality control with clicky switch keyboards where some of the switches won't click. I've experienced this and it is a very very frustrating issue, especially if it happens with an alpha switch.
However, I wouldn't be too scared about this issue because mechanicalkeyboards.com has some awesome customer service, if you happen to be unlucky to receive this issue
Hope this helps.