I've checked the T&Cs for this card and it appears to stack up. You do a balance transfer to the card and as long as you use it to spend at least 25 a month, your transfer rate will stay at 0% forever, until it is paid off. They seem to distringuish between transfer balances and your standard balance (ie, purchases) so there doesn't appear to be an issue of using your monthly repayment to offset against the cheapest rated items first and then start stacking interest on the other more expensive interest rated items.
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