Sigma Designs Super VGA card - any good?

[Larry Campbell]

I'm trying to configure a 486 box to replace my Sparcstation 2 (sigh, don't
ask, I have to have DOS Merge and an ANSI lint, and real X11R4, not
OpenWindows).  I am probably going to buy a Dell box because of good
experiences with their gear and their support in the past.  (Some other
lucky person in my office will inherit the Sparc.)

Now, Dell's top-of-the-line display is their own card, called GPX or
something, which is OK but costs too much (the Sparc was free, but we have to
pay real money for the 486...)  When I complained about the price, the sales
critter offered me a Sigma Designs card, which is supposed to be
1024x768x256 -- same as the GPX -- but about $1,000 less.  Which brings me
to The Question:

Are these cards any good?  What does the GPX card do for $1,000 more that the
Sigma Designs card won't?  (The sales critter was stumped on that one.)
-- 
Larry Campbell             The Boston Software Works, Inc., 120 Fulton Street
campbell at redsox.bsw.com    Boston, Massachusetts 02109 (USA)