Aperture: SSD + HDD. Advice?

I'm installing a 256GB SSD as my main drive on a MacBookPro and a 750GB HDD as my "archive" drive.

How can I get the best performance on Aperture? I've heard about people keeping their library on the SSD and the Masters on the HDD. How does that work? Won't reading the masters on the HDD become a performance bottleneck?

My biggest Aperture library is 400GB so I can't fit it all on the SSD. My plan A is to run my current Aperture library on the SSD and then every 6 months or so, archive my selects to a library on the HDD. Is there a better solution?

The experience so far...

I've now been living with an SSD+HDD configuration for a week. Having the library on the SSD and the Masters on the HDD doesn't really take any advantage of the new SSD to a point worth my investment. I still see the beach ball on occasion though Aperture does feel a little snappier -- perhaps a Mountain Lion or Aperture 3.3.2 virtue and not the SSD at all.

On the other hand, having the full library on the SSD works wonders! Commands are near instantaneous and I can breeze through my library.

So the limitation is on the size of the SSD and the inevitability that it will fill up quickly. I've devised a workflow that I think will work quite well for both keeping my library at a manageable size and improving performance.

I have two libraries on the SSD. Pro Library and Personal Library. The Personal library is linked with my iPhone, iPad and Photo Stream. I sometimes use iPhoto with it but also open in Aperture.

For my Pro library, I'll import and work on all my professional photos on the SSD. My workflow has always been to fly through a shoot adding 1 Star to all the photos I'm going to consider keeping, then when entering the editing phase, I hide all the unrated photos and work on the 1 stars. When I'm done, I go through these selects again and add a second star to all the photos that I will deliver to the client. Some photos get 4 or 5 stars -- 4 is best of the shoot, 5 is all time best photo (I use 3 stars sometimes to add emphasis on which photos will go to the client when I have a big shoot with lots of 1 and 2 star pictures).

I'm going to use this star rating to cull my library by about 80%. Every 3 months or when the need arises, all I have to do is hide all my starred photos and just show unrated pics. I'll Select All and export all those photos to a new library on the HDD which I'll name i.e. "Unrated-Aug2012" then delete those from the Pro Library. I'm left with a much smaller library on the SSD of just my rated photos. This takes just minutes.

This will also help with backups since I'll only be backing up photos that I feel are important and not an additional bunch of fluff that I may or may not ever look at again. I'm creating a vault that will back up my Pro Library but not the unrated libraries (if I lose them to failure, it might just be a good thing to clear out some clutter). I keep 2 copies of this vault. One at home, the other in my bank's safety deposit box.

This system will work well when I eventually do decide to get a new MacBookPro with only SSD storage. It's not imperative to have those unrated photos with me at all times.