iMac in 2009 Summer instead of Mac Pro?

This morning I was talking with my mom about my G4 MDD replacement for her place. You see I stay at her place every 4th week. In March 2007, she said she didn't want to share her computer when I was at her place, so she wanted me to have my own computer for her place. In the end I got a Mac Pro, but for my place and moving the G4 to her place.

We agreed after this purchase that every 2 1/2 years I would get a new Mac Pro at $4,000 and it would be a 50/50 cost split. This morning, not sure how it got started, but the iMac came up and really it is all I need for her place. I am a power user remember, using Aperture, separate OS/Apps and data drives, fast video card, etc. I am at my moms every 4th week and 3 weeks in the summer (I do bring my Mac Pro for that, as well as Christmas 2 weeks).

The problems I see are, I need two physical drives. One for OS/apps (which is also partitioned into 3, OS X, Beta OS, and Windows for gaming) then a large data drive. Of course the other problem is splitting my files or keeping them sync'd between both systems. The last problem is that video card.

The pluses are that she wouldn't have to put out $2,000 every 2 1/2 years and instead put out $2,000-$2.500 every 3 1/2, 4yrs. The downside is I would have to put out the full $4,000 for my Mac Pro every 3 1/2 4 years. Hmm on that account the cycle of Mac Pro My place > her Place would be reduced from 5yrs for the oldest system to 3 1/2 - 4 years, so their are some positives.

We will see It's stil a year away, and honestly I can't afford my $2,000 of a new system for my place for fall 2009.