I have an Ecstasy 101B and I had a 20th Anniversary 6L6 head for about a week before returning it. I know that's not exactly what you're asking for but it's close, so I'll throw my opinion out in case you're interested. I'll assume you already have experience with the 101B, or at least you've done enough homework to know what it's going to give you, so I'll mostly write about the Ecstasy 20th as it compares to the 101B.
Ecstasy 20th - The Good:
I thought the Ecstasy 20th's Green channel was better than the 101B's Green, bigger and cleaner, and the 20th's Red channel was more modern, tighter, crunchier, and clearer than the 101B's Red channel. Actually I think the Ecstasy 20th's Red channel is one of the better modern high gain channels around. It sat right with my 5150's (Peavey OG and EVH 100w Stealth and 100w EL34) in terms of fullness and aggression, and the 20th especially excelled at leads. Full and liquid but still clear, etc. Amazing.
Ecstasy 20th - The Bad:
Where the Ecstasy 20th didn't hit the mark for me, and ultimately the reason I returned it, was because of its Blue channel. It doesn't have enough gain, and instead of the Bogner's signature smooth pick attack splash and greasy smear characteristics, it had a more harsh and hard spike in the highs and high mids that didn't have the bounce and give you'd expect from an amp like the Ecstasy, and just wasn't nearly as fun to play.
IMO, every version of the Ecstasy lives and dies by its Blue channel. That's the most unique thing that amp offers that no other amp really does. When I think of the Ecstasy, when I plug into one, I think of its between-mid-and-high-gain, woody, smeary Blue channel sound and go for that. So even though the Ecstasy 20th has top tier Green and Red channels, to me, $4k is just a bit too steep to pay for an Ecstasy and not get the best version of that sound. Having said that, I also think the Ecstasy 20th's Red channel might be one of the best lead channels ever designed, so it just depends on what you want out of the amp.
TL;DR
The Ecstasy 20th might be the best amp ever made for somebody out there, but to me, it's not the best amp for somebody who wants the Bogner Ecstasy experience.
If it was my money, I'd get the Pandora. It seems more like a classic Ecstasy but with a more tweakable Presence and Depth section and a few extra tightness options in the Blue and Red channels.