A few weeks ago I replace the oil filter on my wife's car, that's been in use for 2 oil changes. It didn't look any worse for wear than when I used single use filters. It's a cartridge type filter. It was no harder the usual to replace. Always been a bit quirky to get off anyway. I replaced it with a 15k mile filter that will see at least 2 changes. I like just dumping oil without messing with the filter so much, I bought an extended use filter for my Exployer. I have to say I haven't noticed any different sound, or way the engines run when using the filter more than on change. Both cars get once a year changes, around 5-6 on the oil.,,,,