Spendor D9.2 vs. Harbeth super hl5 plus xd + REL Stentor III vs. Spendor Classic 100?

What OP said he/she wants:
I prefer precise and high resolution speakers that have control low bass-smooth midrange-detailed treble, with internal imagery and attacks, high-pitched sound and instrument simulation.

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To me OP’s desired sonic traits align better with Spendor D series than classic Spendor or Harbeth. If anything that description of preference points away from classic Spendor or Harbeth, based on my experience. Just sayin’.  YMMV
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for those who may not know the history of spendor, there are few key points, in short form, that are worth noting:

- the hughes family spencer dorothy and son derek owned and ran the company from inception in 1969 to 2000... they developed all sp series speakers, descendants of the bc-1, one of the initial bbc speaker commissions - derek was technical director after dad spencer died too young

- in 2000 the company was sold to philip swift (who founded uk audiolab electronics), swift invested in the company and developed the modern a and d series speakers, to his sonic tastes, which, if you recall audiolab’s sound, was more upfront and lively -- he did this while smartly maintaining and incrementally improving the classic series (the original line) with modernized materials for drivers etc etc - swift is a good businessperson, expanded cabinet and driver manufacturing, serving other makers...

- the surviving son derek hughes is no longer affilliated with spendor the company, has worked for years as independent contractor/consultant and was most recently involved the with the lovely stirling broadcoast bbc ls3/6 - basically an up-market spendor sp1/2 with modernized drivers for better power handling and slightly greater resolution

understanding this helps understand why today’s spendor has their classic and modern (a/d) lines, and why there is such a divergence of sound signature and presentation

here is a useful article for those that are interested ... https://www.spendoraudio.com/wp-content/uploads/Hi_Fi_Choice_Insider_feature.pdf

Maybe the OP would actually prefer ProAc to all of those ?..

I listened D9 and D7 on Montreal Show.
I remember D9 was driven by Chord amplifier and Chord Blu2/Dave CD source. 
The sound was very bright, scratchy and unnatural.
It was modern sound that is exactly opposite to typical Harbeth/Spendor sound that I like. 
If you like a real Spendor sound get SP100 or HL5.
If you like Focal or B&W sound you can consider D9.

Something to consider:  https://www.usaudiomart.com/details/649713712-harbeth-monitor-401-rosewood/images/3150225/