I have the student edition of Altium, but have never had the opportunity to use PADS.
What are your thoughts on the $5k version of PADS vs Altium?
As much as I'm quite critical of Altium, it has become the de facto circuit board design software for many more companies than PADS.
Since 2006, Altium's customer base has risen significantly, whereas Mentor have been having a hard job just maintaining their seat numbers.
It is probably their lack of growth in seats that has "forced" Mentor to reduce their pricing structure. In the early 1990's a full Mentor suite would cost you ~$34K.
If you are in Europe, USA or Australia, your employment prospects would likely be higher if you are proficient with Altium over PADS.
If you are in the UK, then Altium or Proteus would give you the best employment prospects.