With the Recon 3D you're paying for multi-platform support. For just PC use you'll be better off with the Omni.
It could also depend on the deal you're getting. On Amazon the Recon3D is slightly cheaper than the Omni. So if you don't need the beam forming mic and want to have the additional options, the Recon3D could be the better choice.
I agree with Napalm. The Recon has a huge advantage in that you can use it with consoles or PC. But if you aren't going to use it with the console, I think the Omni sounds better. It's not a massive difference, but I noticed it with my Q701 since they're such detail-whores. I think you're paying for the flexibility on the Recon...