Isn't the rating for a 100C rise at 50C ambient?  Or am I misunderstanding?  And I thought it was the Pololus that were overdriven rather than the stepper.  The RepRap guys recommend 1A for the steppers not due to the limits of the stepper, but to keep them from getting hot enough to melt ABS mounts.  Which is a concern for the X axis on the Solidoodle at least.

As I recall, our Y stepper is a little over the recommended voltage. This is actually purposeful, as it solves some performance problems we experienced at the lower voltage. The Y gets hot, but not hot enough for major problems.

I just measured the temp inside of the Solidoodle, with the stock Solidoodle case on,  2 hours into a 2.5 hour print.
Bed was set to 95C and extruder was set to 200C.
Ambient room temp was 68F or 20C.
I used a small pocket IR thermometer. I opened the door and quickly took my readings.

I read max 42C at the top part of inside the case.
Max 74C at the hottest part of the x stepper during high speed movements.
64C at the acrylic part of the extruder.
105C near the center of the bed.

I'm seeing the same. Those temps are fine, with the exception of the x-stepper. The steppers are rated for 50C ambient, but the X-axis is overdriven, so it won't last at 50C ambient, and should probably be cooled at anything over 30C.

Incidentally, it helps a lot to have higher ambient temps when printing large prints.

I read max 42C at the top part of inside the case.
Max 74C at the hottest part of the x stepper during high speed movements.
64C at the acrylic part of the extruder.
105C near the center of the bed.

BTW, I am using plexiglass plates that attach to the sides of the printer sheet metal, rather than the original case, since the plexi sheets are much easier to remove and replace quickly.  Ian had a design which works quite well.