In my experience, suspend would disable the PCMCIA/CF devices
just fine (under 1.5.3 snapshot and 1.6 betas).  However, LCD suspend
(not enabled in the generic kernel) tends to corrupt the shared display
memory, making suspend a gamble.

I had a 1GB microdrive and an orinoco wavelan card, together they used
lots of power and I rarely got more 3.5 hours of life with the standard
battery when in active use.  I bought the high capacity battery and got
a good 8-9 hours.  My solution to save power was to halt the machine and
take out the battery when not in use.  I did this more to lengthen the
life of the LCD rather than worry about power consumption.  Depending on
the condition of your batter(y|ies), your experience may vary greatly.

Hope this helps,
Jolan