Sorry about getting to this thread at such a late time. I own the Quad 2905 ESL's and I'm having a panel replaced in one, right at this moment. I've had two panels per speaker replaced previously but not because of how these were constructed but because of an accidental gain surge via Amarra SQ+.Quad ESL's have always been thought of as high maintenance women and from my experience, the 2905's are consistent with that claim. However, these are made very well with comparison to the 57's and 63's albeit a compromise to the mid-range given the added protective coat over their circuit board. I believe the 63's to be a little richer in the mid-range.
When my repair guy Russ in Northern Ohio spoke with Music Direct/MOFI, given that they recently hired a new sales rep, the rep told Russ that only thirteen pairs of full range Quad ESL's were sold last year in the USA.
My personal view of this is that there's a lack of interest in buying these types of speakers in general, as well as poor marketing from IAG. As for their build quality having come from China, I have no complaints. The Chinese can build a Hubble telescope if you pay them to do it and the 2905's are sturdier than Quad's previous models. Also, coming from China, the cost for these is probably lower than if they were still made in the UK.
Will I buy another pair of Quad's in the future? It's hard to say although as far as there sound, there's nothing to object to. The only reason that I would hesitate on buying Quad ESL"s in the future is the audiophile masochism that comes from owning them. I'll , also add that they are very particular in how they're positioned but I guess that's the price one pays for reference speakers at $14,000 a pair.
I have no experience with Quad's dynamic speaker line but I'd certainly like to hear a pair. It will be interesting to see how the Quad company develops towards the future. My hope is that they'll offer newer breakthroughs in home audio, surpassing the legacy they've already created for themselves.