Anyone use either of these boards? I'm kinda going with the I2C so I can use with my RPi too but I'd like to know if anyone's used the Sparkfuns board. Right now I have 3 servos and a high powered LED so but soon to add more motors. How easy will it be to control the led with either board?
Looking at the Adafruit page, it looks like it is has one or two things the TLC5940 from Sparkfun does not have:
It's an i2c-controlled PWM driver with a built in clock, evidently in the TLC5940 family, you need to continuously send it signal tying up your microcontroller, while the Adafruit, operates independently once given the commands.
6 address select pins so you can wire up to 62 of these on a single i2c bus, a total of 992 outputs
Terminal block for power input so that you can wire up the servos from this power source -- from the picture, it looks like Sparkfun may have this also, as there are two holes in the top of the board, but it isn't called out
I haven't used either of the two boards you asked about. While both seem to be competent companies, I tend to go to Adafruit frist, and then look to Sparkfun if Adafruit doesn't have what I want.
You might also look at pololu.com, which has its own controllers for robots. Here is their Mini Maestro 24 controller: http://www.pololu.com/catalog/product/1356. They also make versions with 6, 12, and 18 controllers.