I've been to Vegas a lot, and wondered how the prices compared to going to Manila as it's about the same distance, just to compare with a non-UK flight I also looked at Vegas to Manila. I used July as the benchmark, and surprisingly all the flights came up priced around £750
I was expecting the Vegas one to be cheaper, which it wasn't, and the LAS>MNL one was a surprise as I thought UK taxes made our flights more expensive, but they are similar from the US.