I have a pretty heavy bike I use to travel long distances with a lot of luggage. It has a mix of XT, deore and other Shimano equipment. I bought it second hand so I don't really know the details. I have ridden 10,000km with it without replacing anything in the drive train, and it's now so used up the chain skips when I apply too much force on the pedals, and my foot just goes straight to the ground.
I want to change the 11-34 cassette and the chain to solve that. On the website I will order from, they have:
a 14€ HG400 Alivio Sora
a 16€ HG201 Acera
a 47€ M770 XT
I have no idea what explains the price difference. As far as I can tell they are all compatible with my XT derailleur but the XT one is lighter. I don't really care about weight as I use this bike to transport heavy equipment anyway, but I do care about durability.
What should I buy? Should I also change the rings at the same time?
Thanks a lot for your help.