My system and graphics card are much less powerful than yours. If I change my display settings to 1280x1024, maximize mIRC and then run your script, my results are:
Cleartype off:
finished (type 1); 50 lines displayed in 297 ticks;
finished (type 2); 50 lines displayed in 1891 ticks;
Cleartype on:
finished (type 1); 50 lines displayed in 906 ticks;
finished (type 2); 50 lines displayed in 3672 ticks;
It's difficult to know exactly why some users experience a greater slow-down. However, I'm not too surprised considering how complex the font-linking feature is. It really depends on so many different issues. I think we will just have to wait until mIRC becomes a full unicode application to resolve this.
