Raptor vs PID

[SmokeBomb]

Shortly after I got my Bradley I purchased a BBQ Guru Raptor, not long after that I started seeing posts for PIDs. One of the things I like best about the Raptor is you can monitor both pit and meat temps, thereby completely removing the temptation to commit the cardinal sin and open the door to check temps near the end of cooking time. I think I understand the purpose of the PID to basically be the same as the Raptor, but less expensive - always a plus! I have a couple of questions though;
a) Is a PID more accurate than a Raptor?
b) I've never seen a wiring diagram with both meat and pit monitors (unless I just missed it - which is quite possible!) everything has 1 TC - is it dual-use? 
c) How do/can you/is there a need to calibrate a PID?
Thanks in advance for your answers.
SmokeBomb

[MRH]

Smoke Bomb,

I put together a PID a while back on mine and really like it.  It will hold the chamber temp within 2 degrees up or down from where I set it.  As far as the meat temp I use a separate meat thermometer to measure the temp there, so both temps are monitored at the same time but with 2 devices.  I can't  compare it to a Raptor since I have never even seen one before.

Mark

[Arcs_n_Sparks]

SmokeBomb,

I put together my own PID and am using one of the two probes from the Maverick ET-73. This way the Maverick displays the meat temperature, and the PID is monitoring/controlling the box temperature.

Arcs_n_Sparks

[nodak]

I had purchased a Raptor but didn't have very good luck with it maintaining my smoker temp (+ or -15F).  So I returned it and built a PID(+ or -3) and purchased a maverick ET73 to check my meat temp and also for remote temp double checking on my smoker.  I really like the mavericks alarm feature as I can set it and go to bed and the alarm goes off when my meat is ready or if something happens to my smoker and it loses or gains temp.

[Habanero Smoker]

I can't compare the two, but I have had good results with my Raptor/Guru combination. Mine rarely varied beyound +5°F.