Wow, I'm really late! But I've been a very happy V-Studio 700 user for a couple years or so. I'm still using X2, as an upgrade hasn't been in the budget this year. I simply adore the whole system. I haven't heard much about X3, but it sounds like the VS700 crowd is fairly happy with it? The 700R is a very fine audio interface, and I love the built-in Fantom. The 700C surface is beautiful and works great, even considering the few shortcomings under X2.
I've certainly had my share of troubles, mostly during the crazy initial setup phase. Yikes. And there are a few niggles that sometimes annoy me and make me wonder, "What were they thinking?" But ever since the firmware updates, drivers and quirks were all well and fully ironed out...it's really been a joy to use. I still get excited every time I yank off the dust cover (courtesy of LeCover.com...highly recommended).