I tried betterdeal for my E92 335 back in November but was only able to get about $500 off the betterdeal listed price on their website. betterdeal did call me and say they had a few dealers willing to sell me a new 335i for $117k + stamp duty (metallic, roof, auto) so i used this sort of ballpark figure to bargain direct with the Qld dealers.
in any case, do you need brand new? if you are balancing between 323 and 325 and can go used 325, i'd definately try to get the 325 used with the options you listed (for same price as 323 new). in brisbane they had a few used E92 325's on the lot for about $92k though i am not sure how many options they had which fit your requirements.