Never used them, but I did email them awhile ago about combined shipping for 2 lips - they replied with "We unfortunately cannot combine shipping because of dimension and weight of the item".
Then I emailed this seller
http://www.ebay.com/itm/130758370844?item=130758370844&viewitem=&sspagename=ADME:X:eRTM:MOTORS:1123&vxp=mtr with the same question and got this response "We do not offer combined shipping but if you purchase directly we can offer you both items shipped for $300 USD.
If you are interested just send us your Paypal email address and shipping address. Write email like this: xcessmotors2010 (a) gmail (dt) com".
Basically neither of them give a shit about opening a box and putting another lip in the box.
Both of those come in under $300AUD anyways, only other (cheap) option is Ultrex.