I need to replace my chain (for the first time). My bike is roughly 4 years old using Alivio 8 speed (24 gears) system. Looking at wiggle they seem to have 3 chains available.
Looking at other questions on here, (for example Are all 9 speed chains compatible with all 9 speed systems?) it would seem that any 8 speed should work.
I would like to ask is there a good reason to go for one or another (they all roughly the same price, within a few pounds).
No, all 8 speed chains are not compatible. For that matter, neither are all 9 speed chains. But for practical purposes, they will be within tolerance to work well enough. Ideal shifting is best obtained with all components being of the same design, in good condition, and good adjustment.
The chains you linked to: There are 2 types of Shimano 8 speed chains. The common one, HG or Hyperglide and IG, or Interglide chains, which are not designed to work together.
If you have HG, and buy a shimano chain, you should get an HG chain.
SRAM chains have looser tolerances, so any 7/8 speed chain will do as well as any other.
I am not saying you can't use any 8 speed chain. Only that some will shift better than others.
As well as the Shimano chains that you have 'linked to' there are also the SRAM chains. These have the 'powerlink' that enables you to put the chain on and take it off a bit easier (almost tool free).
Although Shimano can make a good chain these days, this has not been the historical situation. Because of this there are a lot of people like myself that advocate the SRAM (formerly SEDIS) chains.
Google SRAM 8 Speed Chain and you will find affordable and expensive variants. The more expensive ones have more nickel plating on them, but are essentially the same chain underneath. The basic ones work great.
8 speed chains are marginally fatter than their nine speed counterparts, 8 speed chains should also work fine on 7 speed.
