It was once the practice to furnish gouges with the inside surface refined and polished.  This is no longer the case, generally.  Woodcraft's Swiss tools come highly polished, but the grinding marks are not removed before polishing.  In addition to the quality of steel, balance, and symmetry - look for how deep the grinding marks are in the concave sides of the gouges.  The deeper these are, the more work will be required to get them into carving condition.

Best quality:

• Dastra
• Pfiel (Swiss-made from Woodcraft)
• Two Cherries
• Ashley Iles - I have a few tools and they are nice quality.  I generally prefer the tools above, but just because of feel.  These are nice tools

Medium Quality:

• Henry Taylor (Acorn) - these are well-forged and good steel, but grinding on concave surfaces is usually pretty rough.

Avoid:

• Sorby - I believe these are also sold by Sears.  I have some good turning tools by Sorby, but the carving tools are clumsy, asymmetrical, and the steel has soft spots, making them impossible to sharpen (and very frustrating).
• Speedball - These are cheap tools sold to art students.  I have had a few that have good steel, but generally the tools are too small.  If you already have some, bring them along.  I wouldn't toss them, but they are not a substitute for the larger tools.
• Buck Brothers - They used to make some very nice tools.  I have some patternmakers chisels and long-bent gouges that I would not trade for anything.  However, the new versions are chunky, drop-forged tools that bear no relationship to the old ones.
• Harbor Freight - Don't even think of buying edge tools from Harbor Freight.  If you need something to bend a steel bar or a sacrificial tool, fine.  With carving tools, you get what you pay for!

This list is not comprehensive.  If you have some good, middling or bad tools you want to recommend-drop me a note and maybe I will put them on the list.