I've had the TireGard installed since Christmas '09 and really like it.  Earlier models had issues and a short life but it seems to be fixed.  Super easy to set-up, you just need to decide where to mount it.  I mounted mine just to the lower left of the instrument bezel. ( You can see it on the Push Mountain Videos.)  The main factor on where to mount it is to consider that the on/off button in on top of the fob.  It is not one of those buttons on the front so you can't tuck in in up under the dash. 

I set my tires at 42psi cold.  You can program the upper and lower limits of the pressure to set off a flashing warning.  I have my lower limit set at 38 and my upper at 55.  The tires will get up to 5psi higher in a hurry.  I've seen as much as an 8 psi gain on a hot day.

Temp readout - The front tire is almost always within a couple of degrees of the outside air temp.  The rear tire is consistently 15 degrees warmer.  Probably due to being wider, less airflow and stuck between the mufflers.

Plusses - Super easy set-up.   - Very accurate readout.  I compared it to a high end digital tire gauge and it was right on. - The low pressure warning. - The temp readout. - Tough; Worked fine at 11 degrees F. 

Minuses - Not back lit unless you push a button.  Having said that, if it goes into the warning mode, it will be backlit when flashing.  Must move the bike to get a current readout.  Just roll it a little and it will update.  - No auto shut-off.  Must remember to turn it off when you dismount. - Digits are a little small.

What I really like about it is that it tells me my tires really hold pressure well.  I only add air every couple of months.  It is an integral part of my scan going down the road. 

If a stranger asks me what it is, I give them one of two answers.  If they seem genuinely interested in the bike, it's a TPMS.  If I think they are shady, it's a wireless motion detector with auto remote disable and a GPS tracking antenna.  I'm not sayin', I'm just sayin'....

I got mine here: http://www.motorcycle-atv-store.com/store.php/motorcycle/pd391452/WIRELESS_TIRE_PRESSURE_MONITOR_by_TireGard