ridiculous conditions attached to tracking
The T&Cs say it takes up to 90 days for tracking to take place, so I didn't send a query; however, after 90 days had elapsed, and it still hadn't tracked, the system wouldn't let me send a claim, because it was too late!
After several emails to quido's customer service (the first couple were standard copy and paste replies telling me it's too late to raise a claim), they finally gave in, and quidco has paid me out of their own funds.
Generous cashback rate, but stupid terms and conditions; if your purchase hasn't tracked after 44 days, make sure you submit a claim before the time runs out. They'll tell you your claim is on hold, but at least you've done your bit right!