SPDY + Nginx - Useful When Used?

So, we have nginx + spdy for our SSL requests and responses.

Everything works well.

Unfortunately, spdy is SSL only at this point.

Now our service is quite heavy.

We have the opportunity to quickly make the necessary changes so that requests are sent to our ssl handler, and our ssl reverse handler proxies them to where they need to go.

Does spdy really speed things up? Is it worth it to spend what it would probably be for a couple of hours to make chrome / latest firefox send our ajax requests to our ssl handler and have our ssl reverse proxy handler where they need to go?

Notes:

a) This will only be active for a select group of white browsers (ex: last chrome / firefox). Simple js are easy to change here.

b) Yes, we know how to make http → https ajax requests in these white browsers.

c) From our fairly extensive testing, the nginx + spdy command works quite well. So yes, we know it slightly alpha / beta at this point. A small risk that we are ready to accept.

d) Recall that our service is 90% + ajax. Only the initial entry is served through non-ajax, all other "page views" are processed through ajax. Thus, it has the potential to speed things up for a large subset of our users.

Thank.