I would say the Nord, but I'm biast because I love my NL2. The powerful leads I get out of it are so different to the VC. The Nord is one synth I will never part with.
The Alesis do sound nice though and have more in the spec area with filters and the like, but I haven't spent heaps of time with them, so for me to compare it to the Virus wouldn't be right.
In the end it will come down to personal choice I rekon.
Good luck.
