Alkali was bought by Tron Hockey, so to a certain extent it's a different brand than it was back when the CA9 and RPD lines came out. That said, I owned a pair of Revel 1s for a while and they are good skates. @wickedslappah mentioned, they do not compare to the top end Missions or Bauer's in terms of the stiffness of the boot (the Curv composite) or the quality of the skate, but they are great skates on the whole. Fairly light, nice fit and comfort, the mag chassis are nice (have heard of people breaking them, but same with kryptoniums, so...). The wheels they come with are way too soft for me, but luckily I know some guys at Konixx who were happy to swap the +0s for a set of +2s. If you're really heavy and a hard skater I don't think they'll last forever, but if you're average and playing house league you'll probably enjoy them.
I don't own them anymore, but not because I had any issue with them. [Short story is I moved from NY to AZ in August and for whatever my stuff didn't end up in AZ until November, so I just bought the Revel 1s to use until my gear arrived, and then sold them later].
To answer your question, Wicked Slappah, it's usually about cost. The high end Missions are double the price of high end Tours or Alkalis. Even the second level Missions are a couple hundred bucks more than top Tour/Alkali. I don't disagree that they're not nearly as good, but not everyone has over a grand to drop on skates. Also, a lot of guys I know that are on Tour or Alkali pro teams use Tours or Alkali, but not because they're as good, just because they get them free and don't care if they go soft quick because they can get another pair. Aside from cost, there is a fit issue. Tours fit much deeper than Bauer and Mission, and Alkali's fit close to Mission/Supreme, so some people have no choice but to wear Tours for the fit.