I just installed your HD clouds and for me a combination of two packages works best so far. I picked the 512px cirrus textures from the 64px-package and put them together with the 512px cumulus textures from your 512px-package. This interestingly gave me a fps-boost of almost 10-15 fps compared to staylo's HD clouds, so that I now have around 40-45 fps on my notebook which I'm running Condor on (ASUS Z53SV, Intel Core 2 Duo T7500 @ 2,20 GHz, 2 GB RAM, Nvidia GeForce 8600M GB, Windows Vista SP2).
Usually I don't like that "fuzzy" look of cloud textures, even back in Flight Simulator 2004 I avoided those cloud textures as far as I could, but having your clouds here in Condor I have to admit that the feeling when flying right under your clouds is quite atmospheric. On my short testing hop it really felt like being "packed in" and having something huge right on top of yourself. When you reach the cloud base it is nice how things start to get foggy in a very soft manner, not as sharp and sudden like with other textures.
So, you did a great job I think, they'll be my favorite clouds from now - unless you come up with something still even better!
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