LOVE both of those shows. Also Garage Squad. I think my favorite part is the (apparent) honesty of them. Sure, none of those crews has to shell out their own personal funds for the parts but they're still trying to be budget-conscious and re-use whatever parts they can. The crews even "donate" bits from their own garages to make things happen. The shows where they chuck out and replace anything that's even dusty... I just can't relate!
Also the fact that RKG and EM crews know quite a bit but are clearly learning as they go. On RKG, nothing ever goes as planned. Brand-new parts don't fit and sometimes don't even work. Just like in my garage! The fun part is that they consider the projects "done enough" when the engine puts power to the wheels -- we'll figure out a proper gas tank later! Then they take the half-built heap for a test drive... and break something else on the way home.
I also think that I learn a lot more from those shows. The RKG guys often limp a car along as a problem develops, showing and telling you the symptoms (and guessing at diagnoses) the whole way. Then they tear it apart and find the real culprit. A picture is worth a thousand words, but a video of a car misfiring from a failing coil (as opposed to a failing fuel pump) is worth an entire book.