New 2012's Sora 3500 vs used 2003's 105 5501 I am preparing my bike for a 2000 km trip. I have an old and used ~2003 hybrid bike with 105 derailleurs and want to change the current horizontal handlebars to road ones, so I have to change cables and shifters too.

Some time ago I got an almost new Shimano Sora groupset, so I will use, at least, those shifters for my bike. Do you think I should also change the derailleurs or should I better stay with the current old but nice 105?
After making it to Norway with the Sora groupset, now I regret the change. As far as I remember, the original 105 was faster and I would guess, reliable enough.

I am used to good derailleurs, even though they could be old. For my commuting bike I use a Shimano 600 tricolore from the late eighties and for my road bike I use a Shimano Ultegra from the late two thousands. Once I finished my trip and came back to my other bikes, I realized they are way better, and still reliable even though they are old.

Moral of this story: for shimano at least, it's better old and good than new and bad.