How about S1283 vs TRUE both lapped..? I suppose the TRUE would win?
Can't speak for the comparison as I do not own the TRUE, but lapping the Xiggy made a major performance improvement, I had compared its original performance to my lapped Tuniq Tower 120, and the unlapped Xiggy and the Lapped Tuniq were almost identical performance wise.
However after lapping the Xiggy and to be fair used the Tuniq 120 Fan for the comparison, the Xiggy bested the Tuniq by 5C under load, and that was a pleasant discovery.
Warning: Anyone considering lapping the Xiggy, only lapp to the depth of the deepest existing manufacturing scratches, as you can seriousl affect the strength of the cooling pipes if you cut too deep.