So ive been toying around with the idea of putting a cheap catch can on my daily (05 forester, 2.5 SOHC). I have heard that there is a much bigger benefit if you have a turbo, but since mine is naturally aspirated, what, if any benefits would I see from installing a catch can? 

There really is no benefit.  Your engine is already set up to deal with blowby, adding a catch can is just one more part to maintain (unless it's set up to drain back into the engine, you'll have to drain the catch can), and it's not as if you'll notice a bump in power with the zero-to-half-a-point bump in the octane rating of your inlet charge.

Thanks! I'll skip it then and spend my $30 on something more useful. 

There is zero benefit. And the VAST majority of turbo engines also don't need one. People that think they do either don't or they are band-aiding a blown engine/turbo. 

We have 500 AWHP cars that have no catch can or AOS and are just fine.

GD

NOBODY needs an AOS or catch can on a street car.  If your pushing that much oil into your intake charge, you need a rebuild.

Until the rules changed in the mid/late 2000's Prodrive vented the WRC and Group N car's PCV systems straight into the atmosphere using an under-car draft tube running off the engine.