I too used replkacement hydraulic lifters which I specified to be, IIRC, 25N greater than standard.
They worked perfectly but I became concerned that the final flip of the boot lid might not be good for the metalwork and replaced them with original lifters.
If all the joints and hinges are suitably lubricated, even standard lifters can raise the boot lid fully.
There is a video on Youtube which demonstrates a method of achieving the same goal by usinig a screw on each side of the mechanism to modify the geometry.. I suspect this may well reduce the capabilities of the pedestrian protection system and is not something I'd use myself.