I run Hot Shot's Secret (HSS) and did a run with the Blue Diamond (BD) one time. The BD has a very high molybdenum content and high Total Base Number (TBN - a measure of how well the oil neutralizes acids in the engine) - but I do not advocate extended oil change intervals even though I run a bypass oil filtration unit from AMSOIL and always get a used oil analysis (UOA). The BD could possibly run for longer intervals than other oils as it is shear stable (it maintained the highest viscosity stability and TBN of any oil I've run) but it is VERY expensive and in my opinion the only way to justify the additional expense would be with extended(2.5xT6) oil change intervals.
I won't experiment on extended oil change intervals myself but a UOA does provide insight into whether the oil still has capability to continue providing adequate (preferably better than adequate) protection. Using a Fumoto Valve in the oil pan or a siphon through the oil fill tube provides a way to get an oil sample without completely draining the system. The oil filter may be swapped independently of the oil change as well since it is a cartridge and accessible from the top of the engine unlike a spin-on filter. And as mentioned above, extending oil change intervals without supplemental bypass oil filtration is not a good decision (and is just not a good idea at all in my opinion).
Acknowledging these elements, BD is a fantastic oil in quality. I have enjoyed very good results with the HSS (others swear by Rev-X and there seems to be a growing following of Archoic 9100 as an engine oil additive too - these all address the HEUI tendency to develop sticktion).
I think it is good stuff and the UOA backs that up objectively.