both the pre and the amp are sunfire, so i'd be amazed if the pins were in different orders.
i have the sunfire cinema grand II and the sunfire tgp5 and they sound noticeably better to my ears with xlrs (when fed from other preamps as well).
i also bought some monoprice interconnects out of curiosity when i was ordering some other stuff from them and in my opinion, they will be the weak link in that equation. they're great for what they are - well-priced no nonsense cables, but their sound quality isn't what i would consider top notch. for an extreme example, i bought a 15 foot pair of interconnects to see if could keep a non-remote tuner on my desk (away from my rig) and the sound was so bad when it reached my preamp that i couldn't use them - even for sports or npr.
if i remember correctly, my impression of the knuconceptz stuff was that it was probably better made (but that was just from reading their webpages). and in my system, the monoprice rca connecters were better than the xlr ones, so that seems like it might contribute to the sound.
that being said, i'm sure a shorter pair would sound ok after burning in like crazy (months or years), but they'll never give you 100% of your gear in my opinion. and i never spent the time to burn mine in.
bottom line, though, is burn the he11 out of them and then see. if they still don't sound as good, you could pick up a pair of xlrs from one of our audiogon auction sellers (for as low as $20 and up), all of which would be a noticeable upgrade, i THINK.
cheers
