11's seem to be ideal on my 5120.... heavy enough to keep the floating bridge in place and gives me that nice bottom end tone i like, and yet still comfortable to play for my aging fingers. Since I don't do much for bends with my style of play, it seems to be the best all around!
I use 11's on all my guitars. Still easy to bend strings. 13's for me aren't comfortable. I used to use them, but a guitarist I know, told me that those heavy gauges make it more likely to develop finger problems when getting older
I'm playing 10s on all my electric guitars, and have for decades. About once a year I buy about 20 sets and am good to go for awhile. At home they feel fine, on stage it often seems like I should be using at least 11s.
I used to use 13s (0.14 high E) as well on my Loar with p90s, but it was always open G tuned and I played heavy copper slide on it, so I didn’t need to bend.
Sounded great though. Brand new heavy gauge + high action would resurrect even the dullest of guitar.