Hi!
I'm soon in the market for a new computer and have come up with two different solutions:
1. Buy an iMac 27'' (2,7 Ghz) and a Macbook Air 13'' (128 Gb)
2. Buy a Macbook Pro, 15'' (2,2 Ghz) or 13'' (2,8 Ghz), and an Apple Thunderbolt display
Apart from the the usual Safari, Mail, iTunes and word processing, I use my computer for CAD (Solid Edge in Windows), Rhino 3d and some rendering (Keyshot and Bunkspeed Shot).
After working on a 13'' Macbook Alu (2,4 Ghz-version from '08) I feel the need for a bigger screen but I don't want to give up the portability.
Both solutions cost about the same and I'm not in a hurry to buy anything so I can wait for potential updates.
Which of the two solutions would you go for?
I'd go with option 2. Here's why:
For one: while in college, I had an iMac (Early 2006; 20"; 2.0GHz Core Duo) and alongside it I had a MacBook (Late 2006; 1.83GHz Core 2 Duo). The iMac did everything I could possibly want to do on a Mac. While the MacBook could suffice for internet and word processing, but it lacked the storage space and discrete VRAM-laden graphics on the iMac, which resulted in me not doing a whole lot with it. Sure, for taking notes, browsing the Internet, and playing nothing more graphically intensive than WarCraft III, the MacBook was fine. But I couldn't fit my music library on it. I couldn't do video editing with it, I couldn't play games on it. I ended up hating this as I frequently wasn't at my desk with the iMac. I was often at the then-girlfriend's house or downstairs in the living room, or somewhere else different, and the machine I took to those places just wasn't powerful; plus all of my stuff was on the desktop and I'd have to consolidate files between the two machines; it was a mess. All in all, I began to realize that this wasn't the right set-up for me. For some, it works extremely well. I'm not one of them. If you are, then the first option is the better call; otherwise, I've found that unless you are doing specific tasks with the second one (or making the non-portable one a server), there's no real point to owning two Macs. I've long since gotten rid of the MacBook, and I'm getting ready to upgrade my set-up to a 15" MacBook Pro (when the next refresh comes along).
As for practical reasons, the MacBook Air can't be upgraded. You can order a kit to replace the Blade-style mSATA SSD drive, but it's pricey and voids your AppleCare. Your RAM is soldered onto the logic board, so that's not getting upgraded at all. Similarly, you can only upgrade the RAM on your iMac. Even if you were to gain physical access to your hard drive on your iMac, you'd still be unable to use anything other than an Apple-OEM part as the replacement. The MacBook Pro lacks both of these problems. It also lacks the heat dissipation problems of the current iMac design, which leads to increased unreliability. This is a problem that the Thunderbolt Display does not have. So unless owning two Macs versus one is how you like to have your computer set-up (it's not for me, but if it works for you, then more power to you), I'd highly recommend against it and for your second option.
As for an iPad, I don't feel like an iPad necessarily makes a MacBook Pro, or even a 13" MacBook Air silly as they do different things entirely. I think that even if you go the route of a MacBook Pro and a Thunderbolt display, an iPad is a wonderful thing to have around as it is infinitely more portable than any Mac, and in some cases, that's all you need to take around. I imagine that I won't take my soon-to-be 15" MacBook Pro around to anywhere near as many places as I currently take my iPad around to, but so it goes. That said, if you are the type to take your MacBook Pro everywhere and you have something like an iPod touch or an iPhone that you also take around everywhere, an iPad might be extraneous to you. But that's entirely subjective.