This is the
half swaddle sleep sack that i mentioned
I can dig mine out and send it to you to try out if you want?
My little boy was always skinny and this didn't really have the desired effect but a chubbier chunky baby I can imagine it working better
as for a product that makes him feel swaddled but with the use of his arms also - well really errr nothing I can imagine exists - how about getting a hammock for him to nap in - that way he feels enclosed and cocooned like a swaddle - but he'd not be able to turn over anyway
I swaddled for so long because he hated being on his tummy and didn't roll over until later but mainly because he had bad moro(sp) reflex and would constantly wake himself up and the swaddling helped him sleep peacefully - he had the moro reflex even past 6 months