How good are Scanspeak 13M/8640

I have two pairs of these old gems that I can either re-use or sell. I prefer to re-use them, maybe to cover 500hz to 3k. How do they compare to today's newer offerings? Top 30%? Middle 40%? Hopefully not bottom 30%. I inherited them so I do not have practical experience with them. Thanks!
 

I saw that one. "We have had Revelators and Illuminators after these Classics, but honestly, I don't think a similar system from these drivers would sound any better than what these drivers can accomplish." -- This says more about his implementation than the driver itself. It sounds like that Revelators and Illuminators are definitely better, but his implementation can make the 13M close enough. I do not have his level of skills, so I hope to have a great starting point, if 13M is not a great starting point.
 
Do you still have your Scanspeak 13M/8640? I am looking to buy one or two.

I had one go bad in my Duntech speakers and looking for an original replacement as the other three are good.

Please let me know thank you in advance