besides propaganda, TL-WA5210G on the 2.4GHz wont do the job on a 5 KM PTP (point to point) link
if you have not bought and insist using the2.4GHz crowded band, wait for the new radio read here http://www.tp-link.com/en/products/details/?categoryid=&model=TL-WA7210N
if they wont have it in your country use the radio 7510 read here http://www.tp-link.com/en/products/details/?categoryid=&model=TL-WA7510N that one works in the 5Ghz. that band its not crowded.
check your country regulations on the 5Ghz band.
the link would be 5Ghz band but what ever you connect like your needs, share internet with this 2.4GHz, would have no problem.
But even with the 7510 i still have my doubts, you might have to add antenna, and that would make the link expensier and bulky, like this one http://www.tp-link.com/en/products/details/?categoryid=2474&model=TL-ANT5830B
if you all ready bought the 2 radios, set one as AP and the other as CLIENT http://www.tp-link.com/en/article/?faqid=318