I have been doing some testing for last half hour or so.
a) Seems to be pretty robust.
b) Seems to change modes and refresh rates pretty quickly and reliably - about 8s from 24p to 60p (was 12s in v0.23).
c) I haven't seen any problems with mode switch. NICE JOB TEAM
d) It also fixes another issue for me; at the moment X800 firmware / Netflix app will lock up hard sometimes if HDMI sink is not HDCP2.2 / 4K. With Linker HDCP2.2 sink - no such problem
A few downsides:
1) GUI appears to be broken. Neither the supplied GUI nor previous GUIs can run (I use 4.0 driver version). This means I cannot set custom EDID or other parameters I would like to set to make test the same - I really want to use my own EDID with deep color disabled (as Lumagen cannot accept it)
2) Mode switching is still a bit messy. When the player changes modes often you get a green / white full screen flash, then a small video image in the corner of the screen, then maybe another flash, then the picture. It just looks a bit messy. Makes my system not look "high end"
3) One time on connecting USB power I didn't have any image (BD player was on when connected USB power),
Already it is much much better it seems than previously. So far, very happy. Great support.