Argon is relatively standard insulation inside the diving dry suit for those who dive on helium mixes since helium has very bad insulation characteristics. There is less difference in the insulation between argon and air/nitrox but people still like to use it for an extra warm (some experiments show no difference between air and argon).

The question is how it will work on the surface. Most likely it should work good enough on air and argon will just add complexity without noticeable improvement in the insulation.