Yes the GW Instek GDS-1054Z has a 'better' FFT than the Rigol DS1054Z but the UI on the GDS-1054Z is "Ugh" ...
My point being that, if you really want to do FFT, you'd be better bumping up your budget to the $600 - $900 range.
If you really want to do spectrum analysis, buy a spectrum analyzer.
When I receive your $500 check in the mail, I'll consider your recommendation. Even then I might use the $500 to pay next month's mortgage.
As for 55" tv's, I got a perfectly fine one for $350 a few months ago. And yes, if I wanted to be a tv elitist, I know I could spend over a few grand. I find that some have the same view of scopes.
Consider me in the Fungus camp, or even a few levels below. I have seen videos by audio techs using their scope to measure >0.1% amplifier harmonic distortion using scopes rated fairly poorly for their fft function.
https://youtu.be/n8hNrDcJMCwI was looking for something that is considered the top of the heap with regard to fft, maybe a little or somewhat better than what the audio guy was using for under $300. It looks like the GW Instek fits the bill, with the only downside being a little more knob fiddling being required.
Thanks for the recommendations. The GW will be added to my "maybe" list.