These are the ones I use - no rust and the metal tips screw onto the plastic tips and unscrew for cleaning.
The ones with the syringe tips were making me crazy - soaking in alcohol and water - these are easy to clean with a pipe cleaner or toothpick.
You can buy a bunch of replacement tips pretty cheap, too.
http://www.dharmatrading.com/html/eng/1708-AA.shtml