I've used Slime within Emacs as my primary development environment for Common Lisp (or Aquamacs on OS X), but are there other compelling choices out there? I've heard about Lispworks, but is that [or something else] worth looking at? Or does anyone have tips to getting the most out of Emacs (e.g., hooking it up to the hyperspec for easy reference)?
Update: Section 7 of Pascal Costanza's Highly Opinionated Guide to Lisp give one perspective. But to me, SLIME really seems to be where it's at.
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