@tragedyjones They have so many tricks in their bag - even Covers, a very integral part of their entire splat, contributes to stealth by default. Or spoofing, reflexively hiding from (and being aware of) supernatural scrutiny attempting to figure out your species. Then they have a ton of crap meant to assist infiltration, including borrowing people's likeness, etc.
Vampires of course have the combination of Obfuscate and Dominate (to remove memories of whoever might end up seeing them anyway) which is so very good - plus they don't show up on many forms of photography, cameras, infrared, etc by definition.
Irraka lack insta-stealth (the 'now you see me, now you don't') if I remember correctly. However they can do things coming out of stealth, and they can extend stealth to their entire group which sure is nice. They're not nearly there though compared to the other splats, unless I haven't thought of something.