My Hw98 with standard stroke hold sensitive.
The same gun with V-glide tune hold sensative.
The same gun with 12mm piston stroke reduction perfect.The rifle is in. 177.
My 99s in standard factory set up was a bit hold sensative for me, until I added a Jonny Neate barrel weight (blued steel) and that cured the sensative issue. In 22 cal.
My choice would be the 99s.
Les.