I've used P4D several times, courier that turns up is DHL, always turns up on time (where time = sometime during the day, so you need someone to be around). I've sent side skirts, suspension arms, etc., but make sure you measure the thing packaged up and weighed - it will be the size (length) that will make it relatively expensive, using P4D the quote for sending my rear Cadamuro bumper valance was around £30, so front bumper will be more probably. Wheels are nice sizes and not too heavy without tyres so are more economical to send.
http://www.p4d.co.uk/Signing up for a free account makes it a bit cheaper too.
