In the past I owned the ARC vsi60e and paired it most often with the Vandersteen 2ce and that combo was a superlative match. Never any problems or issues. Currently I own a Primaluna Dialogue 1and use it in my office system. Today I would choose the Primaluna over the ARC because of several reasons: First, the audio bias is so much fun because it makes tube-rolling a snap. The Dialogue series allows you so many tube choices, to name just a few, EL34s, 6L6s, KT88, KT66s, KT77 and many more...I am currently running Russian NOS 6n3ce (6L6 family), going to switch over to some KT88s soon.
Second, the build quality is tank-like, great hassle-free tube cage, good looks, many other nice qualities like Home Theatre pass through. Great built-in circuit protections.
Third, and most important, the amp is musical, again, you can tailor the sound to your heart content. I get a huge soundstage, well-layered, great midrange, singers are life like in size, very good detail, imaging and coherence, warmth and richness without going too far that way.
Fourth, Kevin Deal at Upscale audio is the real deal, kevin is a tube Guru, and he and his cohorts are what all high-end dealers should be...their knowledge is vast and they ship the right way and fast.
To conclude, the Primaluna is a fun trouble free amp that you can easily tune to your liking. As always synergy is key.