The link said iplayer videos only available in the UK so I couldn't try this:
This is a method to rip as .MP4
I now use IE for this.
1. Click Tools â€“ Internet Options
2. In the General Tab, click the Settings button available in the Temporary
Internet Files group.
3. Click View Files to open your Temporary Internet Files folder.
4. Click View Sort by : Size / Descending.Because the file is usually one of the largest.Depending upon the webpage, there could one or more Flash files
(Shockwave Flash Object ,FLV,MP4,etc) This includes MP4 file.
You have to wait for the video on the web site to finish.
5. Once you find the right flash file, right-click and choose Copy. Then paste
the MP4(in this case)file in any other directory.
On YouTube you need to select HQ to get an MP4 from the video.
I mostly have used this for YouTube but it has worked on other sites.Maybe it will for the video you want to copy.