The Maximas are basically bulletproof... if you can get what you have in your Q back out, there's not a particularly good financial reason not to make the switch. Of course, we'd all be better off financially driving Civic's or Sentras - the appeal for the Q is it's sheer luxury and power, in my book it's worth the extra $$.
If I were you, I'd split the difference and buy my Q with 184K for $5K with updated guides, transmission cooler, motor mounts, transmission mounts, shocks, ABS pump, etc...
Heath