Buying used vs new speakers from a technology perspective

Having been into upgrades or mods for over 20 years by far the biggest offense 

in speakers is 90% of all loudspeaker makers use Average to low quality Xovers 

and I am referring to speakers over $10 k . Using electrolytic capacitors in the bass has been used a lot because of cost and sizes ,they are Garbage

and most use $1resistors  and No a resistor is not a resistor sonically.

i use the Excellent $30 retail Path audio , and the New Mundorf Ultra  resistors are excellent ,even inductors many use cheap $6 sledge hammer iron inductors.many great capacitors.out there depending on budget.

i buy a older speaker,a quality speaker under 10 years old , using quality brand name drivers ,and well built cabinet . I just finished a excellent dynaudio tower for 1/4 of the new price .i put in  $1500 in parts and it sounds far better then the current new model. the Xover is the ♥️ and the 🧠of the speaker  and can totally transform a speaker ,the connectors for example most use gold over brass ,vs copper which is not good sonicly vs Copper WBT, or Furutech , also quality of wire give better detail and clarity,Everything  counts.

I remember going to someone's house who demonstrated an Electrovoice 12 TRX speaker installed in his home built bass reflex box.......great sound.

I would really like a pair of AMT 1’s from 1974, sealed box woofer. ESS used cheap woofers in well-designed heavy boxes. The woofers were of the rolled pleated edge surround system, unlike todays cheesy foam surrounds. Rolled edge speaker surrounds do not rot or turn to dust.  I currently have a pair of Electro Voice EV7 in the garage.  I would bring them in, except the vinyl clad exterior is peeling in a crappy way leaving a speaker covered in aluminum foil that is glued to the plywood.  1960s technology that delaminates. 

Someone looking to buy the new KEF Reference META or Blade META is asking themselves the OP's question.

Well, I’m still enjoying my Apogee di-pole ribbon planar Divas from 1994. It takes a significant dollar sum in today’s field to equal them