Ok thanks, Well there are a few folks here and on other forums that have done quite well on gold using the X-70/705, VLF's are not the Ideal machine in Aus but at one time that's all we had, yes there are better options nower days "But" yes it will find Gold and finding Gold with any detector regardless of the brand and model is a real tough job, So don't be put off, You have only got to walk over where someone else hasn't and your in with a chance.
Finding Gold is only part of the enjoyment, being out there together is the real Gold.
That other coil might help and it might not but there again it might just stumble upon the "Foot of Faith" or the other Hand of Faith, Personally I would grab it and take it to the old tailing piles and creek beds and just enjoy ya selves and don't forget to check out up the walls of those narrow creeks ( Up the creek Banks ),
hope that helps,
J.