hi jeremyh,
i believe that the inexpensive pid controllers on ebay, etc. do not
have ramp/soak capability.
the cheapest i could find on ebay was 75.00 and the quality i could not verify.
omega has them for 85 and up. (good products)
i chose solo, 90 and up, because of the software which you can get from this link.
http://ftp.automationdirect.com/pub/slsoft.zip
i think it's reasonable to assume this software will work other controllers.