I guess it's all in perception - I do a lot of Java work on a 2012 MBP 2.3 quad core with 16g and an SSD - still feels slow to me quite often. Have not even considered a MBA because of this.
I have a similar spec 2012 MBP. Are you using Trim Enabler? Otherwise, you may have lost a lot of SSD performance. Also, do you monitor RAM usage? Browsers can eat up your RAM. OS X needs RAM for disk caching for snappy performance.
When using Trim Enabler, you basically have to re-check it after every system software update. (Not apps, but the OS.) I have the app set up start automatically, so I can take a look. I think there are paid options for more convenient facilities.
