I have fully updated P3D 4.5 to hotfix 2 (Scenery, Content and Client) and I am still getting the stutters, however one thing I did notice is that when the sim is paused, it is completely stutter free
I also checked the VRAM usage while testing, and it is around 2.9 to 3.2 GB used, so it isn't running out of memory on the GPU. The stutters also seemed a little less frequent, but still prominant.
One thing I haven't done is completely wipe the GPU drivers and clean reinstall them, if you think that will help, I will do it, but I'm not keen unless it is absolutely necessary
Apart