I am looking at the same move. Have been for about a year now and have yet to pull the plug. Some of my findings:
As a few others have mentioned, the 13" is mobile. I felt moving the 15" was back to the distant days of hauling around a Windows laptop. That extra pound makes itself felt. I switched from looking at the 15" to the 13".
For me, 256 gb would be a non-starter. We travel a lot and use my wife's 256gb Air on the road. Even with a 128 gb JetDrive Lite, an external is frequently plugged in. iTunes music alone is 150 gb, images are 800 gb. Using LR's Smart Previews takes up a lot of space. I'm not an LR user but my limited experience with it is they duplicate existing previews, not substitute one for the other.
Unless you're doing Pro work, the Ezio's and NEC's are overkill. Nice monitors for sure but spec your monitor to your needs. In reality, even in the Pro world you see a lot fewer of these flagships these days. Guys selling stock or retouching high end fashion work do just fine with a lot less monitor.
You might want to spend some time on I/O. My experience with my wife's Air is USB 3 drives (went through 5 with different spinners and ssd's) is they spontaneously eject, improper ejects on sleep and failure to remount on wake. That was with 10.9, 10.10 is no different with the 1 drive I kept. FireWire with 10.10 and the Thunderbolt adapter is also problematic. Lacie enclosures won't eject and hang shutdown, OWC enclosures won't sleep. That's the reason I pulled back my purchase decision. We have over 15 tb of FireWire drives and a wholesale switch to Thunderbolt was not in the cards. I use a utility called Mountain to control mounts and unmounts manually.
Unless your doing a lot of multi-tasking, you're better off with dual-core.
As a few others have mentioned, the 13" is mobile. I felt moving the 15" was back to the distant days of hauling around a Windows laptop. That extra pound makes itself felt. I switched from looking at the 15" to the 13".
For me, 256 gb would be a non-starter. We travel a lot and use my wife's 256gb Air on the road. Even with a 128 gb JetDrive Lite, an external is frequently plugged in. iTunes music alone is 150 gb, images are 800 gb. Using LR's Smart Previews takes up a lot of space. I'm not an LR user but my limited experience with it is they duplicate existing previews, not substitute one for the other.
Unless you're doing Pro work, the Ezio's and NEC's are overkill. Nice monitors for sure but spec your monitor to your needs. In reality, even in the Pro world you see a lot fewer of these flagships these days. Guys selling stock or retouching high end fashion work do just fine with a lot less monitor.
You might want to spend some time on I/O. My experience with my wife's Air is USB 3 drives (went through 5 with different spinners and ssd's) is they spontaneously eject, improper ejects on sleep and failure to remount on wake. That was with 10.9, 10.10 is no different with the 1 drive I kept. FireWire with 10.10 and the Thunderbolt adapter is also problematic. Lacie enclosures won't eject and hang shutdown, OWC enclosures won't sleep. That's the reason I pulled back my purchase decision. We have over 15 tb of FireWire drives and a wholesale switch to Thunderbolt was not in the cards. I use a utility called Mountain to control mounts and unmounts manually.
Unless your doing a lot of multi-tasking, you're better off with dual-core.