Doing some research on spray foam, and came across a few do it yourself kits for home insulation.
Anyone use these?  Thoughts, in general?
Looks 'simple' enough. 

I considered it to do the rim joist area of my house.  Turned out that I could hire someone to do it with one of the big rigs for less than the cost of one of the kits.    

Great Material, I have used the small tank application [2- 20lb. propane sized tanks & about 10' of hose] Works very well in confined/restricted spaces and where a "Big Rig" would involve routing hoses up stairs, thru crawl ways, and small attic access.
Material expands Very Rapidly, and in a matter of 10 or so sq. ft. you can get a handle on dwell time in relation to thickness you want. Tenacious bond qualities to Anything, so don't spray it where you will have to remove it.
Used it [as a stopgap measure] on the interior of a barn built in 1860 with Chestnut siding 4 years ago. Siding is no longer warping, interior is waterproof and I no longer have to continue re-nailing the siding on a mothly schedule. A little on the expensive side, but easy to work with! Keeping the spray tips clean is important. If you stop spraying for more than 5 minutes, the tip will clog up on you. Estimate the coverage you will get out of a set of tanks, and prep for that amount of continuos application. It's so much fun, you'll have a problem stopping. Good Luck

I looked into it a few months ago and found it was cheaper to hire it out, at least in the size application I was looking at (~3000 sq feet of surface area).

I'm looking to do this on top of EPS.  The (recycled) EPS had a good price point.  I'm putting it around the crawlspace walls on the inside.  I'm planning to spray about 1/2" of one of these foams on the installed EPS to seal it against infiltration and to give it a better fire resistance.  This seems to give me a good solution.  Low cost insulation using the EPS, easy (easier) installation since I don't have to cut it too close if I fill all the leaks by covering with spray foam.

Any thoughts?  Will it stick?  Will it work?