I'd definitely get synthetic rope for any winch, which is really the main positive that winch has going for it.
I hate the wire rope for two reasons. Wire has memory... so it kinks up all the time and unspools as soon as you release the winch clutch. And the wire is heavy... so it adds something like 40-50 lbs to the winch. The only good thing about wire is it's toughness. You can run it over a rock and not have to worry about chafe guards, etc.
I considered the Smitty winch too, because of the decent price and that it already comes with synthetic. I read a good number of positive reviews, however, as in any situation, you get what you pay for. So obviously Smitty is cutting corners somewhere vs. the competitors. You're probably getting a little less power and some cheaper materials here and there.
I imagine it will be fine for occasional use as long as you care for it well. Be sure to check the syn rope after each use. I'd also buy a cover for it if you plan to leave it on the vehicle in order to prolong the life of the components. It's amazing what sunlight and rain can do in short order.
I'm also really, really looking into a central mounted winch a la foers winch system, but haven't figured if it'll be possible yet. Do you have the 10k winch or the 8.5k winch?
You'll really be hard pressed to find the room for the winch between the frame rails under your seat. Another thing to consider there, is that you have to find room to run the cable to the back of the vehicle, then run it to the front. The cable requires a straight line... and if you're using syn rope... you can't run it anywhere near anything hot. You also won't be able to get the rope to lay nice and straight in the spool... because you won't be able to get to it... and how would you unlock the clutch? Sorry... not trying to be negative Nancy with the idea... but it would be a huge undertaking.