I'm on the verge of buying Ivory 1.5 PC, however i'd love to know each of the different piano's sizes. I unfortunately am not going to be able to install all 3 as I simply don't have the hard drive space on my 74gb Raptor (too much space taken up by USB and Spectrasonics libraries!!) but I have a good 30gb free so am going to install 2 of the pianos (I'm thinking probably the Steinway and the C7) - but how many gigs space does each piano take up under 1.5?
I was just looking through the Archives and I noticed your post. I thought you might find it useful to know that the more of a Hard Drive you use the slower the latter parts of it become. So, with a 10,000 RPM Raptor (which I use as my boot drive incidentally), you ideally just want to use it for system files, applications and cache files (like for recording).
I have Ivory on a 250GB Hitachi Deskstar and it loads up in about 5 - 10 seconds depending on options.
70gb isn't very much for sample libraries these days, I use 1TB of SATA storage!