I didnt but last time I went to Wembley was Linkin Park and they sounded fine. But Spiritbox I couldnt really make out (yes its screamy music anyway but you know what I mean!) I find alot of the time the support act is abit of a warm up to getting the sound right and by the time the main comes on its fine. Also depends on seating. I know higher up people can complain about sound quality. I always try to get in the lower/middle sections for concerts (think we were in the 100s maybe 113 for LP)
I find arenas where the roof is closed the best for sounds as it all stays in. Ive loved the sound of anything Ive seen at cardiff principality or the o2 in london.
Although saying that,
Gojira and Knocked Loose in cardiff werent the clearest for me, I couldnt tell you what songs they were singing