Joined: Tue May 09, 2006 6:09 pm Posts: 388 Location: Chamonix, France
IMHO yes, quite problematic.
First, they don't penetrate ice as well as steel. Second, you often need to go over rocky sections in your crampons and you really want to have steel ones for that. If you try to climb an icy section with dull flexible points it doesn't have to be very steep to be dangerous.
Aluminium crampons are designed for ski touring and ski mountaineering races, where the crampons are a secondary tool and weight matters. For climbing/mountaineering crampons are an essential part of your gear that you use almost all the time, so it needs to be more reliable/durable/high performance.