no2 is a legal Arganine Alpha Ketoglutarate (or something like that) supplement. It increases nitrogen retention and is a vaso-dialator. Dont expect any special synergy though.
I loved the pump from NO2, but again I was running it with Tren, 19-Nor, and also with a low carb diet, so I am not sure how much of it was associated with Tren and 19-Nor, but it seems as long as it isn't run with Ephederine, you should get a nice pump, as long as diet is in check.
No2 worked great for me but is way too expensive. You can buy 90 caps of l-arginine for 10 bucks so why bother. But If No2 works good for you then it should work great with Var, but as Brett44444444 , don't expect anything special.