thanks, then I think my question applies to cust service TDC - when I've used them in the past there was a larger fare diff than the amount of the voucher - but only on domestic OR internat. - it's been so long that I can't remember which way it is. Maybe on internat all the extra are fees not taxes (?) so I saved more on domestic?

The deal is - I can by a net fare of 512 where I can not use my vouchers - but the lowest I can use it for is 600 (542 + fees and taxes) - so I am trying to figure out if I really loose 88 of the voucher's worth or perhaps a tad less.