One of my Bobs, A. Moody (I like to call her Amanda; she's so fast currently at Driver Class 11, she thinks she's Sonic the Hedgehog!) tried to do what my B-spec drivers never tried to do: win a championship race outside the NASCAR Series (my B-spec level hasn't even reached 20 yet) with a NASCAR stock car (she drove the only NASCAR race car in my garage right now, the Chevrolet "2010 Jimmie Johnson #48 Impala")...and won the first two races...until stupidity struck and I had to quit. She won her first championship race, the Clubman Cup using this special type of car. It seemed after the first few races, I heard a chime followed by audience applause because I knew her Driver Class went up a level. I've noticed that if you put a lower-class B-spec driver in a tuner car or a race car, you can expect to hear a chime followed by audience applause at the end of the race if you coach him/her well.
Another one of my "Bobs", A. Takeda (I like to call him Andrew (Driver Class 12 currently), who drives as if something has possessed him; he's got a personality similar to JoJo's Bizarre Adventure protagonist Jotaro Kujo) won ALL 5 Tuning Car Grand Prix races...in a Chevrolet Corvette Z06 (C6) RM '06 - where the norm would usually be tuning cars.
I've even had moments where my B-spec drivers have had a chance to capitalize off AI opponents' mistakes, like one time an AI opponent in a DOME-ZERO '78 was slipping and sliding at Grand Valley East...and then a few seconds later spun out of control on a straightaway. My B-spec driver never looked back after that nasty pileup the '78 caused.
...and then my first PAINFUL B-spec loss by .03 seconds occurred just a few weeks ago when one of them used a Dodge Challenger SRT8--in the Beginner Series FR Challenge! I tried to quit, but instead, heard the second place jingle and got the cash. I was so shocked, I couldn't even talk for several minutes. I got so mad, I had to retire J. Case (the one in the Challenger) after one race, thinking to myself having a Driver Class 0 driver in this type of race was a very stupid move. I'm a little more careful in B-spec mode nowadays...