poly batting comes in different lofts. so if you like to show off your stitching, you might go for a high loft. if you want a flatter look, there are low lofts available.
they weigh a lot less and some people think they're warmer for the weight, because they do hold in body heat (they don't breathe). every cheapo quilt i ever had had the cheapest poly batting in the world and it never melted in the dryer.

if you like the puckery look of a cotton quilt that's been washed, poly won't do that. the polyester won't shrink enough to pucker. and you should preshrink the fabric before you use it, so the fabric doesn't shrink later and pull the poly up with it. but there's nothing wrong with it. it all depends on the look you want and the feel you like.

I've switched to using cotton batting most of the time for the same reason Damkina did.

Polyester batting is definitely less expensive. I think it's easier to hand-quilt, too. I also don't have a lot of success using spray basting on poly batting. So, if i really need to cut down the cost of a project or i want to hand-quilt i use poly. I just have to force myself to do a lot more basting.

When I'm really squeezing the pennies 'til they scream for mercy, i go to WalMart and buy the bargain brand blankets. a twin sells for less than $5. i toss it into the wash in hot water, then into the dryer on high. it's ready to go. they're too thick to hand-quilt easily, but they work and feel almost like cotton - except for the need to baste closely (like 2" apart with either pins or stitching.)

I use Warm & Natural and love it. I have used poly in a couple of quilts for the fluffy look. I made a quilt that reminded me of a granny quilt and tied it and it just seemed right to use poly for this one. Some times the Warm & Natural is heavy but when it is washed a few times it seems to soften up and be lighter.

I use mostly polyester battings because I like the puffy look and the price is reasonable. For baby quilts I esp. like the batting on a roll that is sometimes available at JoAnn's. (It's about 48" wide and is so much handier to just unroll instead of having to deal with a bigger batt.) My grandkids have used and used their quilts with that batting and it has held up well with heavy use. Recently a friend gave me a high loft poly batt and I'm having trouble with it shifting as I quilt. I usually use a low loft batt and love it for both machine and hand quilting.

It is just personal preference, i use W&N or W&W that i buy off the roll. always with a coupon or on sale. I have the other types, and it just depends on the look i want.
you will see,when you start quilting..just be sure to follow the package instructions for the inches needed in between..

I prefer the polys to W&N. I think the W&N is to heavy & lays to flat for my preference.

I prefer Warm and Natural or Warm and White battings. I use poly batts on baby quilts that I want puffy.

don't the blankets pill? i had some that did and then you could feel little, hard balls inside.

I would use up what you have and then try something else, so that you will see for yourself, I used a cotton batting last time, and it didn't look so 'quilted' but i'm in Great Britain and we don't have the variety of USA folk!

I've used all kinds of batting, until I found my favorite, Quilters Dream Blend. It is 70% cotton and 30% poly. Little more loft than Warm and White--nice for kid's quilts. I can't find in locally, but when it's on sale I buy a big package here: http://www.fabricdepot.com/index.php...ge&pageid=7097
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