I've got a WRX 2004..

would this splitter fit..

Splitter (http://cgi.ebay.co.uk/Subaru-STi-Replica-V-Lip-Splitter-Spoiler-03-06_W0QQitemZ130186333679QQihZ003QQcategoryZ10424QQ ssPageNameZWDVWQQrdZ1QQcmdZViewItem)

or is it for a STI.. as they seem to have different bumper??

Same bumper but you need to fit STi corner splitters to fit that version of lip spoiler.

Can anyone recommend a decent splitter for my WRX?

Look at HT Autos site for the splitter that fits straight on a WRX. It is my car on the website picture with the STI foglight covers on it.

Andy.

Product ID : stilWRX

Look in the group buy section, I think it is still active.