I usually play indoors. The HD500X indoors is reasonably lit...especially with the newly designed led rings around the switches.
However, I just played a gig outside in the daylight and it was not good! This is probably typical of digital displays outdoors and I'm sure it's been said before...my bandmate thought his old digitech board was toast...turned out he just couldn't see his display. I could at least see my HD was on if I got about 2-3 feet from it vertically (bending over at the waist). Quickly changed to the big display format (ie 1A, 1B, 1C, 1D) to make it easier for me...but more so was lucky that all the patches I needed were in one bank...I could've been in real trouble.
Worse...the ring LEDs were completely washed out. This was a big surprise to me...I would've thought I'd at least see something. It was a very bright day, and attempting to move into the shadow of a nearby monitor proved worse...the digital display was completely washed out at that point.
I almost never play outdoors so this isn't a huge concern for me at all, but iit does pose big challenges. Was also using my Variax 89F...completely blind as to whether the Variax was engaged or not due to it being washed out. Luckily there were only 2-3 songs that I was using the Variax models, the rest of the time it was the mag pickups...what a headache...required me to strum the guitar a few times to ensure the setting was engaged before starting the song.