Yikes, I've been away from my computer a lot this year. Lots of outside work time. Sorry for not responding way back in May.
I have over 250 hours on my B3030, and have not once had to adjust the fender mounted joystick cables once I got everything dialed in way back when I first got it, and the main reason for having to do that adjustment was after I re-routed the cables through the floor pan, like is on the cab version (didn't like the cables running outside the floor pan, as the installation instructions call for on the ROPS models) I drilled a hole, put in a rubber grommet, and ran the cables through, and have had no issues since doing that modification. 1st pic shows the modification, 2nd shows the location per the Kubota installation manual.
The optional fender mounted joystick is well worth the extra couple hundred dollars, and is nice when you're doing 6-8 hours straight of loader work.