I've had significant shrinkage from drying my gis in the dryer. If you can avoid it (either because you live in Arizona and can air dry anything in fifteen minutes or because you own three or more gis), I'd avoid the dryer.
Admittedly, the gis I bought were "perfect fits" when I bought them. So any shrinkage at all was going to cause me a problem ... The biggest problem was sleeve shrinkage ...