I found a pitfall to these, when running on dusty asphalt road grime settles on the mesh and makes it much less permeable to air than normally. There was a thick layer of grime on it after one pack and ESC /motor temps had gone higher than normal.
The dusty grime layer is normally the contents of your centre diff!
On balance, it still beats FOD getting into your fans - which is what we discussed previously, right?
I'll take slightly less air flow versus none of my fans working (again!).
I was horrible to my 825 when I first had it. By rights, it really should have melted and seized in the first week of use.
Once I got the shroud and fans sorted, it solved everything.
Even during our Summer, doing crazy speed runs - temps stayed manageable. On tarmac, without the shroud, temps may have been fine - or better even - until a chipping gets in.
And it's not just about running temps - what about those rogue boulders that get in and chew your centre diff up?


The horror of it!
There's no right or wrong to it - it's an option either way. But I'm 100% certain the shroud is a better idea overall. Which is why I run them on my Sworkz as well.