This is not really a discussion about external storage.
Pardon me, I suppose I didn't clarify: I meant you can save on the price of the laptop a bit if you opt for a smaller capacity HDD than it comes with.
My real question was about the ability of the processor and RAM of the Mac Pro. I have a custom built PC with a Sandy Bridge 2700 3.4 and 16 gigs of RAM. I did a lot of research before we purchased the components of this bill. The computer is great but still lags with heavy Photoshop files. From my research this is the best possible PC build out there (at the time of purchase 5/11). And I feel that it's still lacks a bit of performance.
Hmm, that does sound like a powerful machine, I don't know why it would lag, are you sure you have both Win and CS 64 bit versions? Are you running lots of windows open, any malware? Overheating? Also, I heard that SSD can improve performance slightly, I think mostly to do with loading files and such. They're just still too dang expensive for me to try out personally.
Could also try to optimize your CS a bit, found this article:
http://blogs.adobe.com/crawlspace/2011/05/how-to-tune-photoshop-cs5-for-peak-performance.html
My only thought about the Mac Pro would be that this machine would be the only alternative left to purchase for these specific tasks.
Unless you're dealing with real cheapo PC hardware, I dont think a comparable to a PC machine is better just because its made by Apple(their notorious motherboard producer, Foxconn, is also known for making crappy PC motherboards). I know there is an advantage regarding Apple monitors and color calibration, but as far as computing power I doubt there is any real difference in speed. Now there may be other factors affecting your PC's performance, such as overheating, malware, messy registry, etc. etc.. And you just may not want to deal with this, and just get a Mac. Although these days Mac viruses are less rare, I'd say OSX is still a more stable OS in my experience. You dont have to deal with the registry, all applications are encapsulated in one package(prevents spread of some viruses), and the interface is a bit more streamlined that Windows. It maybe also be possible that somehow Adobe products are optimized for OSX, but I've not seen any credible evidence to that yet. I've used both for many years and while I enjoyed my MBP, when I upgraded I opted for a PC, based on a limited budget. SUre I have to reinstall windows once in a while, but I've made an image of my esentials and reload usually takes no more than 10 minutes, and I store all my archive files on an external disk.