Running on a dyno to demonstrate a change is pricey so I understand why it is rare. Running the "torque" program on a smartphone to get a before and after 0-60 run seems like it would be much cheaper/easier and would still be a way to get some idea of the improvement. I think torque also will tell you what it thinks the hp is.
The thread on the main section with a title like "flat dash" has me thinking. A tablet running on the Android software with a GPS and bluetooth can be had for a little over $200 (like the Samsung Galaxy 7 inch). The bluetooth sender for the OPDII port can be pricey but are also available for $20-30. The software is either free or $5 depending on the version. A mount for the tablet is maybe $50. So for about $300, possibly less, you could have torque running and giving you a bunch more information on your car. Additional gauges, 0-60 time, navigation software if you want to use it for that (although my price is a wi-fi which will not work with most droid navigation software). I'm not sure I like the idea of a tablet on the dash, however. It would be functional but I can't figure a way it would look OK.
128i Convertible, MT, Alpine White, Black Top, Taupe Leatherette, Walnut, Sport
Ordered 5/22/09, Completed 6/4/09, At Port 6/9/09, On the Georgia Highway 6/13/09, Ship Arrived Charleston 6/24/09 at 10pm, PCD 7/21/09