Well I only booked one way so was charged 6000+3750 *1.5 for biz class (I couldn't subject myself to SK Y class "service").

Using the miles for this saved my arse* as I had a very cheap BA LGW-KEF flight booked outbound and a pretty cheap FI flight back to LHR and then BA went and cancelled the route leaving me with no options to get to KEF under £150 one way. Unfortunately when I booked the SK flight it was a same day connection and then SK had a schedule change and it was no longer possble to connect same day in OSL from LHR so then I had to book a hotel in OSL etc. etc. That will teach me to book well ahead with BA !!

* FT lets you type arse but not a-double-s. How crazy is that!!!