To set the scene I had a 4000, a 6000, an 8000 and a 12000D Shimano D baitrunner( i sold the 4000 and the 12000 on online shop, since)
About 6 months ago I hooked a kinghy at the wedding cake (Sydney) on the 6000D (IMO this real should be able to cope with a 80cm kinghy, easy)
This reel was nearly new, I dont even think i had caught a fish on it yet,,, I hooked a kinghy, half way throught the battle it stripped all the gears out,, i had to pull the kinghy in by hand with the line,,,,,( the kinghy was just undersize)I took the reel back to the shop where i bought it,,, the boof head there (mind you when i bought it this reel it came with a milllion yrs warranty and could pull the titanic off the bottom,,,so the shop assistant told me) he said "yeah but you had a kinghy on it that is a tough fish for that reel) anyway i took the reel back to Shimano in Taren Point,, they fixed it for free and where very helpful,,,,,,,,I will have the 6000 and the 8000 on online shop shortly,,,I dont trust the D series, one bit.....( imagine you paying out money for latest and greatest gear only to have it fail on your first kinghy??????,,,,DONT BUY A D SERIES BAITRUNNER!) I have MANY B series baitrunners and have never had a problem or this problem with them,,,, i am just an everyday user,,,, not against or for Shimano,,, just telling it as it happened