I had the opportunity to carry out a shock absorbers comparative test between 4 VHS brand new and 4 Monroe after their swap.
Before entering in the tech details it's very impressive the improvement in term of handling and comfot.
The enclosed graphs compare the VHS with eth Monroe at low and high speed in a bump/rebound cycle.
Impressive is how strong is the rebound force provided by the Monroes, that is not good in terms of performance on bumps, the tyre looses contact with the road, as well the Monroe is more sensitive to the speed.
Monroe is a low pressure gas, while the Bil is high pressure.
It's easy to push by hand the piston inside a Monroe (very slow to return) while it's very very hard to it with the Bil.