We don't seem to hear the same stories about the linear engines like the Rolls-Roce Merlin that you do about the radials. Did the Merlin really have a better reliability record ?
Reading WW2 accounts of the B-29 really is amazing, it seems they lost just about as many crew to mechanical failures (principally engines) as they did to enemy action. The Wright R-3350 in it was a real achilles heel. Unbelievable that it was entrusted with the atomic bombs, although I once read that the engines for Enola Gay were specially hand built by development engineers rather than just taken from the standard assembly line. Wright never did seem to get their engines working properly right through to the end of the piston era, despite appearing to have a more compact and powerful design than Pratts.
I read an account by an ex B-29 crewmember who described returning to Guam and there was an enormous pile of junked R-3350s on the edge of the field taken as failures from B-29s (those that managed to get back in this condition), which they had built up with a crane into a single long heap some 20 or 30 feet high, must have been hundreds of engines in there. Would it be unkind to suggest that after 1945 they were all sold back to Lockheed for the Constellation ?
The Pratts R-4360 also seems to have been an engine too far, but appears to have had a lot of prop problems, shed blades, etc, which seems to indicate that it was developing too much power for the prop to handle.