I've got the AR Complete and Twins mkII, the combination is really magical, to say the least. Rich, textured, engaging, and quite powerful. There are plenty of members here and AudioAsylum.com that have this combination and are extrememly happy, especially since I got the Complete with remote control for $650 used here on Audiogon. Don't let that price fool you, the Twins /Complete math is made in heaven.
For me, it was a shoot out between the AR Complete and the Audio Analogue Puccini SE. Both have very similar tonal qualities, but I felt the Complete offered better low frequency control and detail. Although, the Puccini has been updated since then.
But, if you are considereing up to $2k, I would seriously consider the AR Complete's big brother - the YBA Integre. It has all the qualities of the Complete, but even better(at 2x price).
Another thing I highly suggest is replacing the stock power cord with an aftermarket IEC cord. You don't have spend mega -bucks, the $60 Asylum cord works wonders. Or make it yourself, DIY style, it's fairly easy if you can solder 6 wires and will drastically improve sound by removing low level background noise.