I often use a 24" 4k display that I use at 2x and I never had any issue. With other "equivalent" resolutions it may be bad (never tried) but I've heard people c

I often use a 24" 4k display that I use at 2x and I never had any issue. With other "equivalent" resolutions it may be bad (never tried) but I've heard people complain about lag in that situation (even with a newer MBP and apps other than intellij).