i gave some thought to the IXIL's as well bucause of a couple things.
1: they look great without mounting straps
2: the price point was great
3: they look like well made pipes
then i looked and found that the midpipe was a very good design and has a true y-pipe which should split the flow as accurately as possible given that it comes up one side and it needs to be piped to the other.
I got a smokin deal on some used Leo's CF and went with those and they also have a very good mid-pipe design and sound awesome! Very Bassy
Do some research and i am sure you will not be dissapointed with either set, I have not heard the IXIL's though and can vouch for the sound of the leos.