This site is a scam due to google (http://www.gutefrage.net/frage/hat-jemand-erfahrungen-mit-www-cards-exchanger-com, its in German).
I used moneystream.ru for exchanging UKASH to Liberty Reserve (and then to BitCoins
) with success (i found them on a emoney forum where they have also good feedback but i dont remember which) and they also offer PSC->LR . Cashing PSC and UKASH out is always very expensive (especially PSC, for UKASH you can use Neteller which is quite cheap).
Have no idea, found that site by Google (in a sponsored link btw).
Anyway that other site is all in Russian and I see no place to redeem PSC. The only place where it says Paysafecard goes to a blanked out page.