After my first night with the Xelento I think they're excellent - so much detail, hearing extra layers in the mix I haven't appreciated before on many recordings and of course that great bass, which doesn't interfere with the rest of the frequency range. I'd like to echo the reviews which say that it often feels like the sound is coming outside of your head. I find they encourage me stop thinking and listen to the music, as newly revealed deatils catch me off guard and call for attention. I'd say their sound signature is neutral but not sterile. Very engaging but still easy to listen to, neither too warm, nor too cold - balanced. What beyerdynamic does at their best, in the smallest package possible. I agree with the WhatHiFi review - I experienced no initial WOW factor, which would likely become fatiguing with time, they're more refined and subtle than that. When you settle down and allow yourself to just listen the excellent sound quality is there waiting for you to reveal itself.
After seeing close up pictures of the Xelento in detail I couldn't believe how tiny they are in person. My ears have an angled canal/wall at the front so no IEM will sit very deep, the small form of the Xelento helps them to not stick out as much as other IEMs so I can comfortably lay on a pillow and revel in the sound. I couldn't get anywhere near a good seal with the supplied silicone tips, which I'm not surprised by as never have and probably never will be able to use silicone, so have settled on what I've used with previous IEMs - the large Comply foams, without which there is almost no bass or isolation.
The provided cable is very supple and lightweight, the 3.5mm is a noticeably solid connection, and the MMCX connectors with the curved tips for a smooth integration with the ear piece are a good fit. I did find the left cable/ear piece clicked together and the right side didn't have the same reassuring click, although it seems to be well connected regardless. The right side also has two reference dots of where to connect and position the cable, however as both sides of the cable swivel easily when connected I'm not sure it will stay where intended. The magnetically clasped carry case they come with is is lovely quality and functional, with two little cups to keep the ear pieces separate along with a storage box for spare tips, both of which were removed from the Gen2 case. The original black faceplate also looks less like jewellery compared to the Gen2 with its polished chrome and 24k gold faceplate, which for me is a good thing for a portable.
As good as they really do sound I don't think £1k is a good price to be honest. The potential diminishing returns above midrange pricing make me have doubts whether anything much above £500 is a fair price for this or any headphone, although this is my first time trying £1k headgear. I had my ear to the ground as the price dropped on the remaining stock of original Xelentos due to the Gen2 release. I don't believe it's possible the Gen2, at twice the price I picked up the OG Xelento for, will sound twice as good.
If you can pick them up near a mid range price I feel the OG Xelento are worth it for the sound, build quality and the accessories.