Applied the OC to a mobile and a series 4 with identical results and both are running well. Transmission has noticeably more stable speeds using the same torrent. The top cover of the mobile is a lot harder to remove cleanly than the series 4 (all 4 clips broken vs 1).
Relevant dmesg lines (running stock pogo firmware):
BEFORE wrote:Calibrating delay loop... 799.53 BogoMIPS (lpj=3997696)
cpufreq: High frequency: 800000KHz - Low frequency: 200000KHz
AFTER wrote:Calibrating delay loop... 999.42 BogoMIPS (lpj=4997120)
cpufreq: High frequency: 1000000KHz - Low frequency: 250000KHz
Here's a photo
of the sloppy solder job I managed to do with the minimal low quality tools I had available.