Hi, blown insulation is better in my book just for the fact that cellulose is made from recycled materials. Foam is an oil based product and we do not need to be buying more oil. Foam has its draw backs as to later updates or additions. Once you spray in place and it expands you encapsulate everything it comes in contact with ceiling joists, sill plates, wires, junction boxes, you name it. Later on down the road if you want to install a new bath fan or add anything good luck. IT"S ONE BIG BLOCK OF RIGID FOAM, and expensive it needs to be installed by a company that has the equipment, but it does seal all those little cracks. Cellulose on the other hand can be placed by the homeowner and usually a homecenter will rent the machine for free as long as you buy so many bags. Drawbacks it does settle some, the R value isn't as good but you can move it around if you need to make updates and if you add on later all you need to is remove some of it, bag it up, do your thing and put it back. Make sure you wear a mast when installing. Cellulose is treated with a flame retardant and the dust will get to you. Good luck !!