^^ HMM… its a battle game so metal/rock music sound better. ITs also realistic to feel the game in such music as you get more involved and fight like crazy 
medieval type of music is no fun in sword fighting game.. you will only get dull exsperience in such music so for the swordfight/battle games, metal/rock is the must for the excitement and experience
BTW.. even 300 movie got rock type soundtracks (more of a metal).. check/download their OST.. its far away before than medieval period. music is not concerned wtih timeperiod. what matters is type of environment which the game or movie is in. slow/pop/dull music is fading out in this world. Rock is the oldest foundation and it will stay forever 
i hope some1 agrees regarding appealing standards