A steel mounting screw threaded into the alu kickstand may damage, over time, the thread. If you hardly ever placed loads on the parked bicycle, this might be of no concern. If your bike tends to be loaded, though, this is an issue. Also, alu stands generally tend to be wobbly. If I were you, I would go with a steel stand. You also should better have a kickstand plate. If none came with your bike you should look to have one brazed on.