Oldpeddaller

Nothing against new aluminium alloy nipples, but I did have to replace every single one on a pair of used Bontrager Race lite wheels - most were split, some turned to powder when I threatened them with a spoke wrench and others were siezed solid. Only one nipple on a pair of wheels worked - and that one was corroded. My guess is that they had been used in winter (I bought them from a guy in the North of England) and the rock salt spread on the road had caused them to quietly rot away. I replaced the lot with brass nipples and the wheels have been fine ever since. So I'd say if you are likely to get your wheels wet & salty, stick with brass.