JoeN:
GSCLOCK stays for some reason, wouldn't it have been nice if they had put their own oscillator onboard?
From a hobbyist perspective, a weak yes. Having to feed a clock can be annoying. I've been using Clock Output (requires fuse change) and am pleased with the result. It does cost one pin but, if necessary, going to a bigger AVR processor is usually not very expensive.
From the perspective of someone using it to build an actual sign or display, no. The point is to make it easy to keep the processor and LED driver closely synchronized for multiplexing and for eliminating "dead spots".