I used Warm & Natural for one & some type of poly batt for the other (that was 10 years ago & I can't recall!).
W&N is a fantastic product. I only use that & the new Warm & Plush in my quilts, I just quilt much closer together now. I did the quilt in my avatar STID with W&N. I'm planning to pick it up from my sister in September for a week or so in order to add more quilting. I'm doing that with a poly batt table runner, too.
I guess as our society moves more toward cheap, disposable products, a batting that lasts 6 months when quilted 7-8" apart has it's place (which is what I did). As for me, I celebrated the opportunity to spend time adding prettier quilting to some early, ugly quilts, but have definitely learned my lesson & now quilt with no more than a 2" space between quilting lines.
I wouldn't get too nervous, just keep in mind that with any type of batting, the closer together you quilt, the better it will hold together in the washer & dryer.
