I haven't tried it but in theory at least I can think of a couple of reasons why the alloy rack could have an advantage. For sure the binding is caused by dirt. Over time I think the dirt wears a little bit into the plastic, and ends up accumulating faster or more. I reckon with the alloy rack this might be reduced.
I think that there can be some static in the plastic parts which can actually attract dirt, at least it seems that way sometimes, particularly on carpet, and alloy would be better in this regard.
Another possibility, particularly for those like me who race outdoors at night, is that with an alloy rack, particularly a silver one, you can visually verify the thoroughness of your cleaning a lot more positively, as opposed to black dirt on a black plastic rack.
So, I'm not planning on going for the alloy rack, but like I said, in theory at least I can think of a few possibilities why it *might* be better.
Originally Posted by JWATT
The binding is caused by dirt. I don't think an aluminum one will have an advantage.