PCI vs PCIe sound

[MoRT489]

So is there any difference between these two or is it just a matter of choosing the best location on the motherboard? Would be used primarily for gaming.

http://www.overclockers.co.uk/showproduct.php?prodid=SC-049-CL

http://www.overclockers.co.uk/showproduct.php?prodid=SC-052-CL

and is it worth spending the extra £20 to get the x-fi gamer?

http://www.overclockers.co.uk/showproduct.php?prodid=SC-051-CL

 

[MoRT489]

The extreme music is the same price as the extreme gamer, is there any difference?

 

[MoRT489]

seems the xtreme gamer is the newer version of the music with better EAX. Is there any point getting the retail over the OEM? will having OEM cause me problems if it is faulty?