I've long been getting irked with long haul redemption costs, but the seemingly endless sales BA are having of late have simply made redeeming an expensive option for me.

Looking at taking the kids to see The Mouse next August. With a bit of flexibility I can get 4 CW seats LHR-MIA in August. Cost is 500k Avios and £2k. I can get that down to 375k Avios with a 241.

Cash options, I can buy DUB-MIA (various connection options with BA/AA) for £3100 on the exact dates we want. A premium of £1100 but we'd get 76k (ish) Avios in the HHA from the paid option.

The Amex 241 costs £300 to 'earn'. So the premium is reduced to £800. Then there's the 375k Avios. I value these at £1500+, so effectively it is costing me £700 to do the redemption option.

Obviously the direct option is direct, and has the flexibility over the ex-DUB option (which costs €300 to change), BUT as holiday dates are pretty much fixed and any change would likely be a travel insurance job (broken leg, etc.) I don't see that as a huge concern. The cost of getting to DUB from our house and overnighting is generally no higher than driving to and parking at LHR. Breaking the flight somewhere like CLT with the kids is actually preferably as they're still young, and the UA business product is pretty good.

Am I missing something glaringly obvious or am I right that it's going to actually cost me more to use my miles than to use cash?