Haven't had any personal experience, but from what I've read I'd say level 3 will be better than level 1 (as 1 is low & may be effected by the back-of-stage area). Although I'd say Level 2, low row numbers (there's only 11 rows I believe) would be the primo position behind the stage. Aisle 46 should be cool, Edge's side with no obstruction from a CLAW leg.
What row did you get? I believe level 3 averages 24 rows (A being the front), & have seen recommendations not to sit above row J. Also the height of the roof is 125ft above the playing surface. The height of the BONOR spire is 160ft. Looking at the cross-section of the stadium those back rows in level 3 may struggle to see the top of the spire due to the roof. No biggie, but just thought I'd mention it.