I think the short TBO mainly concerned the ones with the Packard internals, there was an article about Jack Roush in Warbird Digest a year or two ago.
The short life span is often associated with overhauls with military components to service limits. Short life is also to be expected with military power settings.
Also, Rolls Royce over the years approved many methods and alterations to extend the service life of parts. Often to the detriment of longetivity.
The last varients produciing 1500 - 1900 hp obviously do not last as long as the earlier lower hp models.
The two speed supercharged ones in particular.
Thats often the case as power output increases with an engine.
I haven't seen it personally with the V-1650 but I have seen it with the R1820 Wright. Was a good engine in the 850 - 1200 hp range. Reliability was abysmal in the 1450 - 1550 range (Super DC-3, S2, T-28C, etc)