Originally Posted by
corporate-wage-slave
You can redeem for a lower cost out of DUB too, to get a more valid comparison / another option. Either via BA, Aer Lingus or AA. Won't work for the 2-4-1 however. On BA that would increase the Avios from 125k per person to 140k, but reduce the cash component from £497 to £282.
If using Aer Lingus the Avios cost is 150k and I guess around £90 cash return. You could fly direct to Orlando and pre-clear in Dublin. So 600k Avios, £360 cash all in. This rather changes the economics in favour of Avios over cash by about £500 using your ungenerous yardstick of 250 Avios per £1 and reduces travel time to comparable to LHR.
Weirdly I knew this, as I recently booked a one way F redemption to DXB out of DUB instead of LHR, as it saved me a considerable amount of cash. Not sure why I've failed to account for it here, possibly because I have a 241 voucher in my account which will lose its "value" if unused, so I've probably defaulted only to options which allow 241 use.
I don't consider the 250/£1 valuation ungenerous, just realistic. That's the general rate I get when redeeming for hotels (or at least I think it is - happy to be corrected if I've got that wrong) and therefore the "cash" value to me.