OK drive for icebook swap?

[PaulKurtz III]

I'm considering the daring task of upgrading my Icebook HD.  I've been
looking at this fluid bearing 40gb Toshiba drive.

http://www.googlegear.com/jsp/ProductDetail.jsp?ProductCode=101606

It's 5400rpm, but I'm hoping the fluid will offset the extra heat.  It's
hard to beat the extra speed AND 16MB of cache.  Anyone have any advice,
cautionary tales, or other info on the subject?  Also, how might it affect
battery life?

Thanks,

Paul