Speakers for ARC REF.1 pre amp, VT200 amp

In my systym, I have great results with this combo and Dunlavy SC-V's and Synergistic Res Ref & Designer's Ref
cabling. I've heard this same set up with Dunlavy SC-IVA's
it's great too, of course your room will dictate what will
sound best.

I have the same gear but different models and the stuff sounds great. Tim is right on target! My gear is a Ref 2, VT 100 mkII, Dunlavy SCIIIs and Synergistic Designers Ref interconnects, and Resolution Ref .5 speaker cable. I would bi-wire the Dunlavys...my dealer said it didn't make that much difference, but I think it does.
Iam using synergistic designer ref. with active sheilding and designer ref. speaker cable to dunlavys sc 4as. Although iam using ss. Ive heard the vt 200 is not the best match for the 4 a,s. the vt 100 is a better match so just a thought?
I have heard that ARC voices with Genesis speakers. I know they have demoed at CES with Wilson Watts for the last few years, and this year with Vandersteen 5's. I have the ref 1 with a vt100m2 and the van 5s. One characteristic of arc equipment seems to be that it mates well with just about any speaker. The magnepan 1.6 was glorious with my vt100. My system right now has wonderful instrument fullness, weight, harmonics, and timbre but is slightly less detailed than my old magnepan 1.6 and audio physic virgos. A benefit of this is that it is less sizzly and more relaxing to listen to.

For cables I have read in stereophile that fremer found the harmonic tech silver cables to be the best match for the ref 2 and vtm-200. I am using nordost spm and red dawn with good results interconnects with good results. I tried the harmonic tech copper truthlink and found it lost a little resolution to nordost spm. Made quite a showing for itself though.
Anything that floats your boat. You have a superb pre/poweramp combination that will drive anything you like. I auditioned the VT200 with my difficult to drive Martin Logan CLS's and it sounded great. Get out here and listen to as many speaker designs as you can, and decide what you like. The ARC equipment that you have will in no way be a limiting factor in your system and is not sensitive to any speaker or cable designs that I am aware of. Good luck, as though you need it with your gear.
I have the ARC Ref.1 with a Plinius SA100MKIII amp and Dynaudio Contour 3.3 speakers. The Dynaudio's are a great full range speaker for this set-up. Also using NBS Monitor III speaker cables, Monitor IV XLR from preamp to amp and Nordost SPM XLR from Meridian 508.24 to the ARC Ref.1
The designers of the Bella Voce speaker by Shun Mook used a variety of amps to voice this extremely coherent 3 way. One combo they used included the VT200 and Ref1 with Nordost SPM, which in the room I heard them in was hard to fault. The BV speaker is seen in Absolute Sound ads and is one of Johnathan Valin's favorites for good reason. As others have said, YMMV depending on the room.
World Class Avalon Eidolon.
Stuart Taylor of ProAc uses Audio Research as his reference for speaker design. There is a real synergy with AR and ProAc, go listen to the Response 2.5s or 3.8s with AR electronics and see if you can do better, I think it will be hard.