Breast density - we want your input

I was told by my GP I had dense breasts during a breast examination.  Breast Screen WA confirmed this when I had my first mammogram but I wasn't offered an ultrasound.  For my second mammogram I had done some research into 3D mammograms being the 'best' thing out, so I requested one.  The cost was over $300 but I fit the age criteria, was on a concession card, and had a 'family history' so the procedure was free.  Interestingly, it was much less invasive than a mammogram and showed a tiny spec in my right breast under ultrasound. The Dr came and had a look and said she was amazed the technician could see it but she said it was likely to be a tiny cyst.  For my third mammogram I suddenly didn't fit the criteria for the 3D ultrasound! I had a mammogram and at the GP's request an ultrasound due to dense breast tissue.  The results showed a 2cm tumour in the right breast, where the speck had been. I don't know if the speck was my tumour or not.  Maybe with further tests if it had been cancer I could have had early treatment and be at Stage 1, not 2.  Anyway, I found a lot of women I spoke to were not aware of the 3D mammogram being available.  I asked the GP why and he said it was expensive and everyone would want one! We have limited machines in WA.  I am considering paying for my 4th mammogram (3D) - it's an amazing machine.  I don't know if I will 'be allowed' to do this - will ask my surgeon when the time comes.  I was just surprised that I found out about 3D mammograms in a magazine - not at the GP's or at BreastScreen WA.  I'd like more info from the horse's mouth in future to make better decisions.  (Whilst on the subject of detecting cancer - I'd be interested to know how many women have been offered a 'thin prep' pap smear rather than the regular?  It costs around $25 and is said to be more reliable.  Who knows? But I read about it in a magazine, lol, and have been doing it ever since.  The GP wanted to know why and I said I heard it was better. He said hmmmm and did it.)