"Wireless" Temperature Probes & Temp Controllers

First, I'm a new egg user interested in the referenced items. I will not be doing anything professionally, just personal cooking for family/friends, etc. I own an XL BGE. FYI, I presently own a cheap digital thermometer with a rubber sheathed probe that can set high and low limits. I just stick the probe through metal top to sense dome temp. Additionally, I have fork type (The Charcoal Companion) with a digital readout that takes 20 or 30 seconds to get to temperature (which seems like forever when searing) to sense internal meat temps.

Temperature Probes

Am I correct that all the available "wireless" temperature probes contain the probe connected to a sheathed cable which penetrates the BGE to a device outside of it that in turn transmits wirelessly. If the answer to the above is yes,  who are the manufacturers and what should I expect to spend on one with at least two temperature inputs. What about a Thermapen vs temp probes for sensing internal meat temps?

Temperature Controllers

I've read the reviews on the Naked Whiz site.   I'm not sure I'd opt for the fancy dancy, operate the cooker remotely deal but I might if someone of experience knows why it makes. It seems that if you could set a temp (simple controller) and have it hold the heat within the advertised range, that would be sufficient as long as you checked on it and when the meat's at temperature remove it.  Again, I'd like input on what I would expect to spend on simple vs sophisticated controllers (maybe a price range). I'm guessing that If you have to buy a temp device to measure the meat temp, and a controller for the BGE temp, a one stop solution might be the best operationally as well as cost effective.

Some stupid questions; 1) How do you get all these probes into the BGE. 2) What is the temp limit on metal sheathed cables/probes (nobody seems to advertise that)? 3) Do they work when searing at high temps without burning up the probe assembly?  

I'd appreciate any iinput before I go waste a bunch of money on stuff that doesn't work.