Agreed.
Sometimes budget is more important than perfection. You know you will match things up later and buying new mains will definitely give you the biggest bang for your buck right now.
Try the CS10 with the M80s for a while and if you find it really distracting then you can always run with no center at all (phantom center) until your next budgeted upgrade comes along. If you sit in the middle, you still get a great center effect. Those who are too far off to the side will be a bit off but how many friends houses to you go to and watch a movie where they don't have a center channel? Did it really bother you that much? Probably not.
Then you have the fun of future upgrades to reach the perfect system.
Non-rambling version...... If it makes you happy, Do it!
