Ok
First are all dies interchangeable between presses?
Example: I have a lee challenger press, do I have to use lee dies or can I use RCBS or Redding dies?

Second I bought the lee pacesetter die set in 30-06 to start with. I now want to reload 308 as well, so can I get the Lee deluxe set and use the 30-06 factory crimp die to crimp the 308 necks?

and finally I am in the market for a new scale. I settled on the RCBS model 502 scale(it seems like it has the best feedback for $70 and under.) any opinions?