I have experience with some early/mid '90s carbon/Al road bikes with Al forks.. in that context they work well, countering some of the "dead" feel of the early carbon. It will probably ride "harsher" than a steel fork. In terms of durability, Al will not bend back like steel so it has to be stiffer to start with. So the Al fork ought to perform better in crashes, up to a certain amount of force, after which it will permanently deform and become junk. If the fork is well engineered and you don't crash much, I'd say you'll be fine.

The first generation of Al forks got a bad reputation for failing (search for "death fork"), make sure it's newer than those.