[wattson12]

it works for a lot of cases, e.g. buy a book and get other books recommended, not so well for rarer purchases like laptops or phones.

[joosters]

I still get recommendations for the same book I just bought, but in different editions/formats. Seems like it could be improved some more.

[dingaling]

But be careful of the 'Perfect Partner / frequently bought with...' recommendations, which Amazon themselves disavow as being in any way compatible:

If two items listed as Perfect Partner / Frequently Bought Together are not compatible, Amazon.co.uk are unable to accept the return of either item for this reason.