I've been a fan of Halo since we had our third son.  They have really brought swaddling and sleep a long way.  No more worrying about how to keep baby warm in spite of it not being safe to have blankets in their beds!  What do you do when they start walking though?  I know my little guy didn't want to be in a sack anymore.  Introducing the Big Kids SleepSack!  Now their little feet stick out but otherwise it is all the same things you loved about a wearable blanket! Such a great invention!  We have the blue.  I only caution you to not size up they run just a tad big so stay to your true size (unlike you would with jammies!).
*disclaimer I received a product to review however this is my honest opinion.  You can see my full review at astheygrowup.com.