it becomes slower when i'm working with photoshop and illustrator at the same time with big dpi images size. to make it comfortable again, i need to turn off all the other apps except for PS and AI.
my machine is 2011" core i5, 256gb ssd, and 4gb of ram.
but the slowness isn't really that bad that i take the thinness of the air over the mbp anyday.
So you've sacrificed thinness over productivity and longevity of performance in ownership?!
MBA 2011 corei5/256GB SSD & 4GB RAM vs MBP 2011 Corei7/500 or 750GB HDD & 4GB RAM.
Lets see:
Immediately performance gain for saving large files while mobile, more powerful dual-core cpu even if its a corei5 in the MBP; the Corei7 2.8Ghz is $100 cheaper than the topline MBA 13" Ultimate.
Productivity oer time = performance:
(Lets say 1-3yrs with AppleCare)
Upgrade Storage: It'll cost you $1000+shipping for a blade SSD for MBA to go double (480GB SSD). MBP costs less than $700 for same 480GB (or 512GB SSD) with same peformance.
Upgrade RAM: woops sorry cant do that on MBA so you're stock as Mountain Lion and more powerful Adobe Suite and similar apps increase in performance and features requiring more RAM. MBP ... ugprade to 16GB official Max for $130.
All prices stated are Canadian; currently slightly higher than US$ value ... and I'm shopping online locally which means you should be able to get much cheaper prices on SSD. with MBP you still save $400 vs upgrading your MBA for better performance - unless of course you upgrade to a new MBA which means more than $1300US.
weight ... barely a pound difference and I'm sure changing to an SSD in the 13" MBP you'd barely notice it ... unless thickness is a concern for you. The ONLY gain you get with MBA is the slightly higher resolution vs the 13" MBP ... I had the ultimate and for Logic, Office 2011 Suite (all running on corporate LAN), Safari, VM access via RDP (Windows Server 2008 R2's) and soon XCode the RAM limitation and exhorbitant SSD Blade costs tipped my hand to trade for 13" MBP Ultimate.
PS: I cannot STAND the 750GB HDD WAAAAy too slow.

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I'm a med student who would be replacing a 2010 MBP. The biggest demand would be having 4-5 very large PowerPoints open and photoshop and watching a video at the same time. My current computer starts to lag when I open iPhoto and try scanning through the images, or when I'm starting up new programs. I doubled the hdd size but it's at best equal in speed, maybe a little slower.
If still under warranty:
Upgrade the RAM, and switch to a 256GB SSD for $319 (Samsung) on Amazon. Wait until summer promotions ... sell it for decent quid (due to dedicated video card) and ugprade to 2012 MBA ultimate.
I owned a 2010 15" Hi-Res MBP with 256GB SSD and I was incredibly impressed as the speed was equal to the 13" MBA Utlimate I owned. Going from a 15" to a 13" MBP/MBA is like night and DAY!
I can imagine just how much 15"MBAir Pro's Apple will sell with high end dedicated video cards, 3x 3.0USB, 1 ThunderBolt, SDXC Slot and FW800 for those that still require it.
