I haven't done a LH flight in Y, ever. WT+ is my norm, and if I upgrade it's usually using Avios or AUP. In terms of Y travel, it tends to be up to 3 hours maximum so LAS - DFW for example (but that is MCE so a little better). I once refused to do LHR - LAX in Y for work. I am not saying I would never travel Y for long haul but I would certainly prefer not to.