There is no difference between the Jabugo ham and the Iberian ham because  Jabugo’s ham is an iberian ham. They come from Iberian pigs with and without race mix.
What it happens is that the ham from Jabugo (Huelva) has obtained a lot of  fame and  there are people that think that it is a superior quality than Iberian ham.
This is wrong because Jabugo provides good Iberian hams and bad Iberian hams, so to talk about Jabugo’s ham does not means necessarily to talk about quality hams.

If we want to eat a good Jabugo’s ham, we first must to know if it’s a bellota ham (The highest iberian ham quality), which is the manufacturer and how it elaborates the hams.