The problem is, to replace one side lower control arm bushes with yours, would cost $285, when you include postage.
http://www.ebay.com.au/itm/291853458...%3AMEBIDX%3AIT
plus you have to buy a non urethane rear bush which will cost a further $50.
http://www.ebay.com.au/itm/322208258...%3AMEBIDX%3AIT
So to do one side with your bushes and a non urethane bush will cost about $335.
I realise it isn't comparing apples with apples, but a set of components to do both sides, that is two lower control arms, can be had for $125.
http://www.ebay.com.au/itm/6-FRONT-L...gAAOxy4XNSRlC~
Therefore one side can be done for $62.50, that equates to five changes of bushes.
Like I said it isn't apples for apples, but it is a hell of premium to pay.
By the way I have used the cheap ones and the rear bush flogged out in 50,000 k's, but your kit doesn't supply the rear bush anyway. The other two bushes are still in service.
I guess what I'm saying is at the exchange rate and postage cost, from my perspective, they aren't viable unless you have money to burn.
What I would suggest would be to offer a complete matched set at a price that makes them attractive, I would certainly consider a set at $200 per side, but I understand that may not be viable from your perspective. But $285 for two bushes is IMO outrageous, just my opinion.