USB net adapters overtook cardbus years ago and dominate the adapter world. They are commodity status and you should have no hesitation making the switch. Use Newegg reviews + sales to find one that sounds good. Recommend ignoring the 'stars' rating: actually read the reviews and look for observations and/or praise which gets mentioned by multiple users. Discount 'it sucks!' and 'it rocks' type reviews.
One of the great advantages they have is ability to employ a USB extension cord and position the adapter itself in a position and location for best transmission/reception. I've a 5" 'gooseneck' cord (stiff so holds position) that lives in my travel bag and has countless times made barely usable signals entirely usable just because I can twist and tweak angles to ideally orient the internal antennas.
I've owned and/or given to friends/family
three of these* (fast, one ran too hot): »
www.newegg.com/Product/P ··· 33166031one of these (solid): »
www.newegg.com/Product/P ··· C1324651one of these (total crapware): »
www.newegg.com/Product/P ··· 33186012one of these** (too hot, flaky performance) »
www.newegg.com/Product/P ··· 33315091and others I can't recall.
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* no longer available but Rosewill has a similar 2-antenae 300mbps
** recommend avoiding all the nano sized ones. No reason to go so small and all seem to have "runs hot" complaints