Conclusions
SPC product codes are extremely simple yet a highly effective method of channel coding.
Randomly interleaved SPC product codes perform even better than SPC product codes, at low SNR, and can get as close as 1.1dB away from capacity for code rate 0.66 and a blocklength of 10,000 bits (BER = 10-5).
PCC and SCC SPC product codes perform quite well for three dimensional codes, and consequently have smaller blocklengths and slightly higher code rates.
Irregular SPC and RI SPC product codes perform even better than the original codes with a small loss in code rate.