NStorm has been around for a while and is a respectful site.
As for viruses, they can come from ANY site if things go wrong or someone hacks the site in some way. Therefore I run a scan on everything I DL, even things from this site. Not that I would think that this site would have a virus but same thing, things can happen. I figure even if it had been true about NStorm that it would have been taken care of quickly as would it be if it were to happen to WC.
I also have played all the Elf bowling games and I love them. Frogapult, is also a fun game.