Viscaria is one of the best if not the best composite blade in terms of rubber synergy. This means you can use any rubber that you like. If you enjoy using hexer then i suggest staying with it especially since the playing characteristics of viscaria is quite different compared to your previous blade. The only rubber which my friend and I did not like on this blade is the Stiga Airoc M. Rubbers that works quite well include Ternergy series, hurricane series and Evolution series which most people use. But seriously dont worry about rubber synergy as it works well with practically anything.