Very interesting, thanks. The reason I am considering the Tiger Foam is the ease of installing it. They have some very detailed install guidelines and it sounded like it would work well in an enclosed wall space. Gutting the sheetrock would be easy and just using std insulation in the one room I want to do would not be hard other than the mess....and the added work of redoing the sheetrock. The main divider wall I want to do divides the house and is 2 story. sound deadening was my main goal there and removing the sheetrock would be a real project as the wall is next to the stairway.
Easy is in the mind of the beholder, but it takes a bit of practice, and it's 3x the cost of cellulose or fiberglass. The slow-rise pour stuff is definitely NOT easy to get right without infra-red imaging and a lot of patience. The spray stuff isn't rocket science but you need to keep an eagle-eye on the temperatures to get consistent results, and a botched job is a complete PITA to hack out and fix. The stuff is pretty rigid and sticks like glue (very similar chemistry to Gorilla Glue) - it adds a lot of structural rigidity to the wall too.
You can dense-pack blown fiberglass and get slightly higher R value than cellulose, but it's not clear whether the acoustical dampening is as good with dense-packed FG as it is with cellulose. It's largely about density, but I'm not sure what densities you can achieve with blown fiberglass before the R-value begins to drop. With cellulose R-values start to drop at densities of ~4lbs/ft^3 or higher, but it's hard (impossible?) to get those densities with a cheap rental blower. 3lbs is pretty easy, 3.5lbs is a bit harder but often achievable.
Cellulose @ 3lbs/ft^3 has better acoustic attenuation than urethane foam @ 2lbs/ft^3 simply by virtue of being 1.5x the mass, and it's dramatically better/denser than any fiberglass batting. If you're serious about sound breaks, staggered-stud double stud walls with dense-packed fiber fill, and a secondary layer of gypsum glued on with acoustic dampening cement (Green Glue, et al) will knock it back well over 50dB, but that doesn't seem like your goal here (or is it?)
If you're good at patching 1.5" holes in sheet rock, dense-packing cellulose is pretty cheap easy & effective compared to gut & replace using 2lb foam in the 600 board-foot kits, and easier to get right than slow-rise foam. One hole per cavity, it's not a huge patch job.
If you're still hot on the foam concept, if it's more than 1000 board feet, between the respirator (mandatory, unless the prospect of inhaling expanding foam doesn't bother you), extra tips, & tyvek suits, it's usually cheaper to call in a contractor who REALLY knows how to spray 2lb foam. Like I said, the kits only make economic sense for very small jobs- the foam-guys usually come in with an installed price lower than your material costs for the just the foam. (In my neigborhood it's anywhere from $1-1.25/board foot, depending on the size of the project. The slow-rise 600 board-foot kit yields only 517 board feet (if you're perfect at applying it, which you ain't), and runs $610 , or $1.18/board-foot even before they've applied the shipping. The spray-on 600 board foot kit yields 600 board feet, or $1.02/board foot before they apply shipping.
I've looked at it several ways before, and it's never made financial sense NOT to let the pros do it on anything bigger than a sealing job. Most of the pros will also try to talk you out of slow-rise pours (half-pound or 2lb stuff), and practically make you sign the waiver before they proceed. I take that as an indicator of just how easy it is to screw up cavity pours, and the pain involved with fixing it when you do.
I ran a half-pound pour-job by a few foam contractors on a project at my own house a coupla years ago. One guy quoted an obscene price, 3 submitted no-bids, another refused to bid based on some of the intra-cavity obstructions, and told me flat out that I'd be insane to hand my money over to the other guy, and that I should dense-pack it with cellulose instead (he isn't in the celluose biz either.) I took his advice, dense-packed it myself, and never looked back. But the whole bidding process quite instructive- if the pros wouldn't touch it, I wasn't inclined to discover why on my own time using an overpriced kit. YMMV.