you could probably just check the product stats from the manufacturer's websites for each product. They will definately have stats like signal range there.
The Apple products are usually a tad pricier, but they generally are very high quality (especially as of late).
Also, Linksys is a smaller company (most companies are smaller than Apple) so they may not have as good customer service and support.
Apple are selling their cards at a higher price for one of two reasons:
1/ Their cards may be better, or
2/ They are playing off their brand name.
choose wisely friend.

cheers!
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