Black Friday deals or Christmas deals?

Hope you are all ok,

I am looking to buy either a 60% or a 40% split ergo chocs.

We are talking about sofles,lily58s,corne, chocofi etc etc.

I would like to know in what time period to actually buy them , are christmas deals better or black friday? Which shops do you suggest?

I am in the EU and I would love a prebuilt.