Speakers for leading edge, transients, speed and big sound

Uhm the M2 is what you needed? Why have you let go of it? @saummisra 

Anyway if you're open to actives, this - https://aaltospeakers.fi/en/product/taipuu-speakers-3-tie-dsp-aktiivikaiutinpari/

Rockport speakers have outstanding transient response.  There is a pair of Rockport Technologies Cygnus for sale on Audiogon - this is a $65k speaker on sale for $36.5k.

i have the Atria IIs, two levels down from the Cygnus, they are totally transparent and have an ability to retain resolution over an amazing dynamic range.  They will happily play at any level your hearing could stand and at the end of a piano piece you can hear when the dampers touch the strings.

If you Google - Rockport speakers transients - you will get a good description of the sound.

The Cygnus and Atria models use the same mids and tweeters, the Cygnus has beefier woofers.

As you move up the range the cabinets become even more advanced.

@saummisra

Check out the Classic Audio T-1.5. Ralph Karsten of Atmasphere has them. They are beautiful and probably sound spectacular  I would love to hear them. Good luck! 

You could pick up a beautiful Volti Rival in custom veneer of your choice brand spanking new within your budget. All the dynamics, speed, accuracy and room filling sound you can want. Plus you don’t need heroic amplifiers to do so as they are super efficient. Just check out Volti website, a multitude of veneer and grill cloth options.