No, .sit files won't get corrupt on a PC.

I've been using that method for months: downloading stuff on my brother's PC, then transfering them to my mac. Works fine. ".sit" stuffit-archive files are data fork-based (contain no resource fork information) so they're safe to transfer to/through a PC.

As long as you don't try expanding the .sit file on the PC (using a PC version of Stuffit Expander) and try to copy the uncompressed stuff over to your Mac. Most of the time that won't work. If the .sit file contains files/applications that have resource fork information it'll be lost. The resulting uncompessed files will most likely be corrupt and useless. Just copy the .sit file to your mac and unstuff it there.

One thing to watch out for are .img files, which are Disk Copy disk image files. .img files _do_ contain resource fork information, and downloading them to a PC will strip the the resource fork information from the file and render it useless. It's frustrating, since the amount of that resource fork data is tiny, like less than 4 KB but it's essential to the file. If you want to download a .img file, you should download it directly to your Mac using Limewire. You could also look for a version of the file that is in a different format or has been encoded to preserve resource fork information. A file like that would probably have a .img.bin or .img.hqx or .img.sit filename extension.

Hope this helps....