Well i have both of them so i can tell you the features:
10th Sonic Screwdriver - Very small and lights up as a torch and has sound.
11th Sonic Screwdriver - It expands, has sound, lights up like a torch, bigger than 10th Sonic Screwdriver.
So in my opinion the 11th Sonic Screwdriver but its still up to you as isn't my choice
The tenth Doctor's screwdriver is better
try Thinkgeek.com
Its common.
The sonic screwdrivers from the second doctor to the tenth doctor were made by the doctor himself but the eleventh doctor's sonic screwdriver was made by the tardis because the tenth doctor's sonic screwdriver wouldnt work.
Your question isn't quite clear, but if you are referring to the screwdriver River has when she meets the Tenth Doctor: the Doctor from the future knew River was about to go to her death (remember they keep meeting out of order). He gave her his screwdriver because he knew his Tenth self would need it to save her. As for why it looks different, every time the sonic screwdriver is destroyed irreparably, the TARDIS presents him with a new one and sometimes the design changes. Improvement: I might know what you mean. River's screwdriver does look quite similar to the Tenth Doctor's blue one, as apposed to the Eleventh Doctor's green one. Which is a strange thing really, but I suppose that the future Doctor would have purposefully given River one that looked like the Tenth Doctor's, so it would make sense to the Tenth Doctor. WIBBLY WOBBLY TIMEY WIMEY!
Sonic Adventure 2 on Dreamcast
Doctor Who The Doctors Revisited - 2013 The Tenth Doctor 1-10 is rated/received certificates of: UK:PG
Sonic Adventure 2. I remember because I got a free cd and coin for his 10th anniversary.
The Tenth Doctors hand was chopped off by the Sycorax leader, in the first Christmas special, entitled "The Christmas Invasion".
It was due to the fatal dase of radiation he'd received.
Sarah Jane Smith got her sonic lipstick from the tenth doctor in school reunion. k-9 was blown up so the doctor reprogrammed him, while leaving Sarah Jane a sonic lipstick, her alien detector watch and a spare sonic lipstick.
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