GAP Insurance etc.
No doubt this is an absolutely cracking deal. Very tempting
Just bear in mind, early trade-in will not be an option, due to high negative equity and purchase will also not make sense, so hand back at the end of the agreement is the only option that's financially viable. That's when mileage charges come in. Mis-calculate and you could be in for a fairly large bill....depending on the per-mile rate and the actual mileage obviously.
Often increasing the PCP mileage is more cost effective than going over the agreed mileage and paying excess, so do the calculations.
Also 'return to invoice' GAP insurance is an absolute must on a deal like this as theft or a write-off at any stage would leave you with massively higher outstanding finance vs. the car's insurance value.