They are a performance network, so you get payed for conversions mostly. So you need good banner location and quality traffic to make good money. Its that simple, every site has a different performance. I made over 25k a month with Xtend, so they are good. But your site need to be good too.
i got about 1000 clicks per day with adsense but my site is warez and i want to use xtend my traffic is from europe - ballkan how $ can i earn?
You will not make any good amount at all without google. eastern europe doesnt pay any good at all. Sorry to say it, but there isnt any good alternatives except if you got tier1 traffic like .us .ca .au .uk etc..