There is another thing to keep in mind here tho:
Yes a RAID array would increase speed overall, but you will need a RAID card unless its on your mobo already.
Second, if you have 2 seperate HDs, they get filled up faster individually of course. And that being the case, you should know that as you fill up a HD, you run into degradation in seek times. As you near the last i beleive its 20% of a HD, you get like only 50% of the performance (check those numbers...im trying to remember exactly, and dont yell if im off..but i wont be off by much~!)
Synopsis: If you go can go RAID, yes you may want to, aside from that tho, go with one bigger drive.
I will admit tho, with the sizes im seeing of the new super huge HDs out there..i dont know how much seek times will slow down when looking thru 80 gigs or more. Unless the RPMs go way up. Id say, if you were thinking in terms of 80 or more, then yeah get yerself 2 40`s and go RAID (cause you could prob afford it, and make use of it as well..or else what in the hell would you need an 80 gig or more HD for..? LOL)
But if your thinking more in terms of one 40 or 2 20`s, or even one 60 or two 30`s..and you dont wanna go with a RAID, then id definately say go single.
And defiantley go IBM 75 GXP..theyre the best IDEs out there now, hands down.
Rama
" He who (BLEEPS) nuns, will later join the church " Joe Strummer, The Clash - "Death or Glory"