I am seeking help again.

I hear a rattling noise from the engine when driving a little briskily. Could it be the bonnet deforming because of the aerodynamics and hitting against the front strut brace? Anyone else experienced this? It is quite loud and reverberates through...can be heard with windows closed.

If that's the problem, I imagine some sort of rubber on the strut brace should resolve it?

Many thanks all!

You could tape white paper to the underside of the bonnet above the strut brace. Cover the strut brace with a good layer of grease. Take it for a drive. If the white paper has grease on it then you know it has been touching. If not look else where for rubbing marks?

The grease and paper can be removed easily.

Ever since I fitted my strut brace I have a vibrational noise as well, but only at low revs/idle. I believe mines is the plastic engine cover touching the top of the strut brace ever so slightly, I just haven't got round to doing anything about it yet.

I did lift the bonnet to investigate though and revved the engine, noticing that the engine moves considerably enough to clear the brace and stop the noise. Maybe your engine cover is getting closer to the strut brace as you drive harder?

Have you tried removing the strut brace to see if it goes away? if so, it will be contact with the strut somehow, only thing it could be in that case would be the engine movement, or that black box on the far left where your strut bolts on, I noticed on my one that the metal bracket touches it.

Hope that helps!

Thanks a lot for the advice, guys. I will investigate and report back.