Regardless of cost, the Shimano Baitrunner is the reel that everyone has copied. Having said that the 'B' series is a solid performer. Lots of improvements over the 'A' series. I plugged with the 'A' series for a couple of seasons and the only reason I changed was I began to lose the anti-reverse (not a hard fix, but not something you want to do at 2 am)). At the at point, I found the Spheros 8000 and always have it w/ me when I am out whether fishing it or as back up). I plugged w/ the 'B' series off and on since then and just tend to grab my Spheros most of the time. The lever release is very handy when you reel in too far in the dark and clink in the swivel! Save me having to grab the braided line to pull and slice up fingers (started to wear sun gloves to stop the cuts and use those all the time regardless of time of day).
I use a Shimano Thunnus 6000 off and on as well and find it works great, but it is very heavy and the body is huge with sort of small spool and rotor! Upon close inspection it is the same body as the 12000 and 16000! Lots use them for tuna and they hold up and send them in for service. Baitrunner has tendancy to get tossed after a tuna season of abuse.
Fishing reels now a days wear out from the elements and not because a fish beat the pee pee out of it ..... LOL.
Personally I rather use a conventional outfit if possible because I can get much more drag pressure, no line twist and my thumb is better than any bait runner feature out there.
You can power in a fish faster, too.
If you want to try out some reels before you buy them give me a holler.
