Anyone have any opinions regarding the STM32F4 series versus the NXP LPC4300 series?

The Cortex-M4 core is pretty much the same across all vendors, so I'm more interested in which has the better peripherals, vendor support, documentation, etc.

 

I can only speak for STM32F4 since I have never used NXP chips.

I am very impressed with the chip itself and the support provided by ST.
There is a community forum which was able to help me resolve any technical difficulties.