Is there any cons to use @font-face?

I found @font-face is good alternative of sIFR3 but every browser need different extension of font. so implementing is more than sIFR3.

But very good thing is FLASH and Javascript not needed.

Is there any cons to use @font-face in compare to sIFR3? I need compatibility in all A-Grade Browsers.

and

If any font which is freely available as a download on net or if font is purchased and provided by client or font is purchased by my company. in all condition can i use those fonts?

Solution

You can use @font-face with:

Firefox 3.5
Safari 3.2
Chrome 4.0
Opera 10.5 http://a.deveria.com/caniuse/#feat=fontface

For IE, the fallback is working great, but be sure to use the little hack for smooth rendering: http://allcreatives.net/2009/12/05/smoother-font-face-embedding-in-ie-7-8/

Issues :

Font rendering quality differs from browser to browsers. As anti aliasing techniques of each browser are different : http://www.position-absolute.com/articles/html5-font-face-is-not-as-ready-as-you-would-think/ Typekit will provide an online tool for that : http://typophile.com/node/65656
_{(source: typophile.com)}
while the font is downloading, the user see the default font during 1 or 2 seconds
If the font is provided by your client, He may be concerned by the fact that the font will be downlodable from the website.
I've made printing font-face tests : it is just not working (but with sFIR it's ok)