I have the Brother SE270D (Disney) and the Brother PE700II. The 270D is only a 4x4 but it's also a combo machine and sews great!! The PE700II is embroidery only but has a 5x7 embroidery area. The 270D uses a memory card and you need the PED Basic software. The 700II has a USB connection straight from computer. No extra softare needed to transfer designs.
One thing if I could afford it would be to get one with a larger embroidery area, but then the price starts going up dramatically.
That being said, I love BOTH of my machines. They are both refurbished so I saved about $100 on each.