Experience with Tannoy Westminster Royal Gold Reference

I own these great looking speakers for a few months, and i am looking for views on its sound quality and people who have long experienced these speakers with different amps, electronics, and rooms, etc..
Based on my short experience, it seems that they are very easy on power quantity as being very efficient speakers, but require absolute quality watts to sound their best.
It feels as if they have infinite potential for sound quality and power, as long as you have what it takes to feed them, so how far can i, should i go with these in terms of associated equipment?
I hope that experienced audiophiles out there can help me realize the full potential on these beauties.
Hello to everyone, I am a newcomer on this forum. I am based in Belgium.  
Please excuse possible language approximations, English is not my mother tong.
I currently own a system consisting of:
- Tannoy Westminster GR
- Atma-Sphere preamp MP-3 and amp M-60
- PS Audio Perfect Wave SACD transport & Direct Stream DAC
- PS Audio power plant and power cords
-Townshend Fractal speaker cables

I am wondering if, after 3+ years or so, @hddg could comment some more about his experience in combining Tannoy Westminster GR with the Gryphon Mephisto monos. Any new addition on the front of the preamp? Maybe someone else with the same type of upgrading experience will jump in and share his thoughts with the same loudspeakers.
Thank you all in advance.

I cannot comment on the Gryphon other than that I can see it is very expensive stuff at 60k for each channel and should better be superb! Regardless of the specific amp, I think the Westminster deserves that kind of power and current delivery. It can handle it ;-)
This is why personally I use the ASR Emitter II Exclusive (about 25k) with the Tannoy Westminster GR and I could not be happier. But I have not heard them with even "better" amps so who knows... Perhaps you should also consider a better source with more detail and less added distortion than the PS DS, like any of the dCS units ;-)
Thank you @arisholm for sharing your thoughts.
Your amp, the ASR Emitter II Exclusive, seems to be quite interesting, I must say. I have the feeling those Westminster need much current to shine, hence my interest in the Mephisto.
I was told by the Gryphon's dealer to start with the Mephisto stereo amplifier first, keeping in mind the stereo can serve as one of the two mono ( after a return trip to factory)  should one decide to upgrade for two mono's. The investment is therefore, at first, more in the range of 60.000 USD.  I am quite anxious to find out whether those Gryphon will do the trick for those big Tannoy. @hddg, if you ever come across this thread , feel free please to comment on your own long by now (?) experience.
As far as the PS Audio DS is concerned, I am not sure it deserved the bad press it received on the audiosciencereview.com forum. Here again, I can't wait checking out the very famous Gryphon Ethos.