FYI, Little known but Strobe Utility gives you some "PureXP latency tuning" capability.
Tip: Intentionally make the crosstalk very bad at the bottom edge of screen; to reduce input lag at the crosshairs location.
While Blur Busters Approved is all about strobe quality, not many people are aware that Strobe Utility can be used to tune the input lag of PureXP in a "quality-vs-latency" tradeoff basis too.
To reduce PureXP lag
a little bit, adjust strobe phase in Blur Busters Strobe Utility until the crosstalk is very bad at the bottom edge. This will reduce screen-center PureXP latency slightly, for those 240fps 240Hz VSYNC OFF use cases.
BenQ DyAc+ also changes input lag too, if you use the BenQ/Zowie version of Blur Busters Strobe Utility --
www.blurbusters.com/strobe-utility (hit "F" key if it doesn't detect your BenQ monitor, and try both Profile A and B). BenQ/Zowie strobe phase is more latency-priority than ViewSonic's strobe phase which is tuned quality-priority, which is a smidge more lag. But those esports-priority, can adjust the lag of PureXP+ screen centre, to match DyAc with a bit of Strobe Utility re-tuning.
The latency is lowest immediately above the crosstalk-band, and highest immediately below the crosstalk-band.
You can also turn off Strobe Utility's built-in TestUFO, and use a faster motionspeed (2000+ pixels/sec) at the web-based version of
www.testufo.com/crosstalk -- to more easily see the crosstalk band on 240Hz-360Hz+ monitors.
Strobing is a latency gradient along the vertical dimension, due to the global-flash versus the LCD scanout (not all pixels refresh at the same time on an LCD panel), which creates some interesting latency modifiers whenever you enable strobing.
TL;DR: Strobe tuning can be a latency-versus-quality tradeoff
Your mileage may vary. The Blur Busters Strobe Utility is also available for BenQ monitors too.
This post equally applies to all strobed monitors supporting a variant of Strobe Utility, whether you're using a BenQ Zowie DyAc+ monitor or a ViewSonic XG2431. They have different strobe tuning defaults. But you can pretty much tune DyAc+ worse lag (but better quality) and PureXP+ better lag (but worse quality), if you wanted. The range is big enough to overlap. The youtubers/testers simply used default strobe phase, and XG2431 is more optimized to strobe quality over strobe lag.
But you can reduce PureXP strobe lag by following the instructions above! And verify for yourself with devices like OSRTT or LDAT (etc).