The Petzl Aztarex is like politics: it's all about compromise. Petzl's designers chose their tradeoffs wisely in this case, producing an inexpensive, lightweight tool that can perform everywhere from alpine snow to vertical ice.
At only 17oz a pair of these will save you a full pound over a pair of Cobras. For alpine use, put on a lighter slipknot leash like the Lockdown and save another quarter-pound for the pair. The lighter weight is great for alpine use, but the tool will require more swings on hard ice, so keep 'em sharp. Like I said, it's all about compromise.
The Aztarex has a good bend to save your fingers and reach around bulges. It also has a pinky rest that releases with a screw and can be stored inside the shaft so the tool will plunge better. Since the leash should be taking all your weight anyway I just leave mine off. All told, this is the tool to have for long alpine routes with some steep ice thrown in, and it won't break your back or your bank account.