1| The
FX-8350's stock clocks are 4GHz so I''m not sure at this point what your overclocking endeavors are.
2| What sort of a kit by XSPC have you found that is in comparison to the H100i and is available for $160? I think you're talking about the 120mm version of the XSPC kit...?
3| You'd also need to go into the watercooling sticky(linked in my sig space), scroll down to the TDP calc(onward) section to understand the TDP and heat dissipation you're eyeing for when you want to go with a custom loop. You'll quickly learn through calc's that the Corsair's H series of coolers(and pretty much every CLC out there) aren't that great of a deal when it come to the watercooling tag line.
4| Can you please pass on your full systems specs? You may have a better endeavor going with air cooling if budget is a constraint while Corsair's AIO's are recently seeing a lot of flak for QC though.