Ok--just talked to Lee Epperson, a huge Doctor Who prop collector. He said, "David Tennant used a toy sonic in the 50th Anniversary episode."
Lee is incorrect here. As masterjedi322 correctly noted, they used an MFX metal replica, not a toy. This has been confirmed by Neill Gorton of MFX, and set photos, as well as the episode itself.
In the Matt Smith and Capaldi eras a CO toy was used a few times for scenes where the sonic would be dropped, to save the real prop from damage. Episodes like in Rings of Akhaten and Deep Breath. I'm sure there was more, but the CO toy was never used for anything long term, and never became the full time prop. It was used for stunts only, and by the nature of filming, a couple close ups for those same scenes.
In The Eleventh Hour, they did not blow up a CO toy, they blew up a resin stunt prop that was made using mods from the CO 9/10 sonic prototype (which was 1:1 scale with the real prop, unlike the CO toy that was released for sale). These molds were given to the show for use in Series 2, however, they never used them in Series 2 or 3, but they were used to make stunt props during Series 4.
For Series 1-3, Mark Corduroy made stunt props himself, without the use of molds from CO. One of his stunt sonics can be seen in The Lazarus Experiment when the Doctor throws Martha the sonic.
Also, the old story that Tennant used a CO toy in The Christmas Invasion is false. He very clearly uses the Wide Slider Aztec.
And as others have noted, some fan made and official replicas, as well as CO toys appeared in Series 10 on Capaldi's desk, and even Nardole used a CO 5th Doctor sonic. And the War Doctor's sonic was made from a CO 4th Doctor sonic.