when available, the wristbands gives discount off the price on the door, which is always €10 more than the final online (or street) pre-sale - which itself is likely to go up in the days leading up to the party. The current pre-sale price is the cheapest you will get, period. Plus with our T&Cs in the rare situation where a party does decrease its prices, we will actually refund the difference automatically (and, no, I doubt any other platform and certainly not any street seller, will extend that platitude)
The golden rule of thumb is: if you dead-set WANT to go, buy online in advance. IF you want to be a bit more spontaneous, take the chance on wristbands being available on the day, but remember that you can still buy with Ibiza Spotlight and then cancel up to 24 hours in advance for a full refund - no questions asked