Tools, Sharpening and Power Machinery - A pneumatic equivalent to Bosch electric Demo Hammer?

I had the pleasure of renting a Bosch 1131EVS (http://www.boschtools.com/Products/Tools/Pages/BoschProductDetail.aspx?pid=11316EVS) Demolition Hammer with a spade bit for a productive session of landscape modification -- in this case, to help with the installation of a 3' retaining wall.

http://mdm.boschwebservices.com/MDMCache/English%20[US]/t06/0000000/r00696v6.jpg

While the Bosch hammer was superb, the $50 rental fee wasn't so hot. I've got a capable compressor on-hand and am wondering if the chipping hammers that pop up on Google searches will work in a similar capacity?

If you have a 25 cfm@100 psi compressor it might be capable of operating an air jack hammer.
This type of tool is very efficient when electric but no so with air.

Here is one of the smaller air hammers I have seen but use a considerable amount of air for a home compressor.

Click image:
http://www.harborfreight.com/cpi/photos/99700-99799/99792.gif (http://www.harborfreight.com/cpi/ctaf/displayitem.taf?Itemnumber=99792)
Image courtesy of harborfreight.com

Here is an inexpensive electric one that should last for quite awhile in limited use:

Click image:
http://www.harborfreight.com/cpi/photos/93800-93899/93853.gif (http://www.harborfreight.com/cpi/ctaf/displayitem.taf?Itemnumber=93853)
Image courtesy of harborfreight.com

The main advantage of a pneumatic tool is in the weight and size. It matters if you have to hold and operate it 8hours/5days. If rental price is your concern, just buy the Bosch that you liked. It's probably cheaper than a comparable air hammer anyway.