I believe the later model LS3 can be had with a remote. The balanced model sounds like it's uneeded for your case. As far as sound quality it may be very close. The ARC I think should be better but that old Adcom was pretty darn good. The service from ARC is excellent and of course build quality is too. I wouldn't worry about whether or not it had a detachable cord or not as I suspect the engineers made sure the wire was more than large enough to handle the little bit of current a preamp may be called on to draw.
Audio Research LS3 owners....
I have seen a couple different versions of this preamp...one with Balanced outputs and detachable pc...the other with RCAs and standard pc cord...is this correct? I assume they had different retail pricing when produced...at any rate...would this be a significant improvement over an Adcom gfp 565 or am I splitting hairs? I am using an late 80s Belles amp as power...thanks...