Question about Power meters?

For the ergomo you 'might' need help installing it untless you know your way around bikes and know how to calibrate it. The Power Tap is pretty simple to install. BTW, most PM already include everything you'll need. Oh, for the ergomo just verify that your cranks/BB are compatible other wise you'll need to buy new cranks.

I would also add that the PM is just a neat toy unless you understand how to use it. To that end:

Training and Racing with a Power Meter

Cycling Peaks

Check out an earlier discussion on Ergomo versus PT :  http://www.beginnertriathlete.com/discussion/forums/thread-view.asp?tid=57735&posts=29&highlight=Ergomo&highlightmode=1#M585082

I installed my own Ergomo Pro and it was fairly straightforward.  The key is getting the wire exiting the bottom bracket to be oriented in the correct position.  They provide spacers of varying widths and you must play around with different combinations of them on the bottom bracket to get the correct position of the exiting wire that goes to the computer mounted on your aerobars.  It took me 4 different tries to get the right combination of spacers.  If you are not mechanically inclined you might be better off having your LBS do it - BUT they must be aware of the setup requirements (i.e. wiring orientation).  Don't just hand them the box and say, "here install this".

I installed my Ergomo without the use of a torque wrench.  The instructions provide specific torque ranges that you must stay within to tighten the bottom bracket.  I basically guessed and went on feel.  I recently bought a torque wrench that I'm going to use to re-install the Ergomo so that I'm confident it is tightened correctly.  The optical unit in the powermeter can be affected if the bottom bracket is not tightened correctly.  As mentioned above, before purchasing make sure the Ergomo will be compatible with your cranks - the dealer you purchase from can tell you that. 

Also the job goes much easier if you have a bike mechanic stand, which also comes in handy when you enter settings on the computer (zeroing requires pedaling the cranks - I forget the term they used for this procedure).  I probably made this sound a lot more complicated than it really is.  Good luck.

All the previous posters have made great points. Any power meter that you buy you must make sure that it is properly installed and calibrated to get accurate numbers. Another option that you might consider is the iBike. I am currently testing one and if you aren't in a hurry I will be writing a review of the product in about a month or so. It sounds like you have done your research on each type of Powermeter. Make sure that you choose the device that fits your needs the best.

If you are interested check out the iBike at www.ibikesports.com .