The problem with the Bathurst weekend is the $5,600 is just your entry fee. By the time you factor in the brakes, tyres, fuel and other expenses it's an easy $10K excerise.
I'm doing 2 rounds of the Dutton this year for less than $5,600 (given I'm splitting the costs with my co-driver). But for $10Kea we could do the whole National Championship and get to drive Queenslannd Raceway, Morgan Park, Wakefield, Eastern Creek, Collie, Barbagallo, Winton and Sandown plus a bunch of other great driving venues.
Driving Bathurst would be awesome but given a very limited motorsport budget there are other things I'd prefer to do.