I wonder what kind of strings and tension do you use for your Head Prestige Classic 600? I have two classics: one (PC600 - designed in Austria) strung with Gosen OG Sheep Micro 17 at low 50s while the other strung with some cheap synthetic at low 50s also. The one (Prestige Classic - made in Austria) with cheap synthetic seems more crisp and responsive. Does this make sense? It's possible that the Prestige Classic (1996) is stiffer than the PC600 sold by TW in 2006 time frame.