I guess I can follow the OP in their attitude to things they haven't done before.
I haven't flown my LHR-PHL-LHR segments in my TP run on BA CW (upper deck, 62K and 64K, so I get to compare them)... but I'm sure it'll be amazing and I definitely won't experience the aforementioned shortcomings
I'll report back in August
And if it really sucks I will split my airline tickets between OW and *A. No need to make a huge fuss.