If you are comparing a $299 Xbox vs a $299 PC, the Xbox would outperform the PC in terms of gaming. That being said, I do say to the OP, its best to save your money and build a good gaming PC that would outperform the consoles.
I say $700 is decent to start (excluding monitor).
You can get the 250gb model for 200$ so that's really cheap.
Move on to PC gaming, better graphics, better mods, better controls.
It's literally better everything.
If he can afford a good gaming PC,absolutely.I played morrowind on PC and with Oblivion,i bought it on xbox360 first and a few years later i bought/played the GOTY edition on PC.I'am probably going to do the same thing with Skyim.