Man I gotta tell ya the MJ2 Gumby combo is outta this world to my ears my friend. As far as tubes go I havent tried the SS tubes yet as I have been enjoying some high end tubes I got from @TK16 and @AuditoryCanvas . And yes man I have never hard my Xs sound so good. I mean seriously the LCD-Xs are an amazing pair of cans. Since I have had them every single upgrade I have made to my chain has only made them sound better and better. I boggles my mind that I still havent reached there limit.
Yes the X is truly an incredible device. Obviously by far the best bargain in the entire LCD lineup. These cans with a really competent amp and dac are hard to beat.
As sick as the LCD4z are (and i4 also) there are no flies on the X at all. If I couldn't have gotten the 4z and i4, I would not worry about that. Systemic balance at a really nice price point is readily achieved by these cans at under $1k, with say another 4 or 5k in the dac, amp, cabling and that figure could be substantially less if judiciously buying good used gear. And then end up with just a smokin' hot setup for personal audio that will provide for untold hours of listening. In fact with a known quantity such as the X, more capital can then be allocated towards upstream chain development. Potential for putting together a really incredible cohesive top-flight system with this approach (utilizing final drive element of LCD-X) at a serious cost efficiency becomes a reality. And this point is one that beginning or even mid-level audiophiles should be aware of.
I just couldn't get rid of my X. Just too much sentimental value there.