Is a 1.4GHz Macbook Air worth it?

I'm willing to buy a MacBook. I'd use it to code and minor photoshop and video edit stuff.

I live in Brazil - Macs are really expensive here.

I found some deals and I can get a 13" Macbook Air 1.4GHz i5 4GB Ram 128GB SSD for R$ 3250 - ~1200 dollars. However, i'm afraid of it's performance. I can get a Retina 13" MacBook Pro i5 2.6GHz/8GB/128GB SSD for R$ 4300. That's a huge difference, but If it's worth i'm willing to save money and buy it.

What are your suggestions? Thanks!