Box for mine has a date code of DF (Apr. '06), another box I've seen had a JE (Oct. '05) date code, so it's safe to say they were produced in late 2005 through early 2006, at the very least. Some question as to whether they were a "Sprint Run" or just "limited production" and how many actually were made. Does seem to be one of those rare cases where SE is more popular than PE. SE version stayed in the lineup till replaced by the FRN Native V and that's only available in CE and SE.
Not allowed to answer "what's it worth" type questions here, but, I think it's fair to say that, as with most older Spydercos, "collector" value depends on three things, rarity, condition, and interest level. Rare is generally worth more than common, "Like new with appropriate box" is always worth more than even "lightly used, but neither rarity or condition mean much if there's little or no collector interest.