allowed commands on keys that keyservers handle correctly

[Realos]

>> If I like to remove my signature from a certain key and/or uid, what is
>> the best approach to that? Does it make sense to revoke the signature or
>> just delete it? I find both of these commands in "gpg" software but am
>> unclear what to use.
>
>You need to revoke the signature once you have lost full control over
>the public key (i.e. uploaded it to a keyserver).  Deleting a
>signature/uid or key makes only sense if you can replace all copies
>with the updated one.

Replacing an old key with updated one seems to be possible with
biglumber and such other servers. Such servers have the disadvatage of
not syncing with other public servers and only allowing one public key
per email address. 

Are there any other drawbacks of Biglumber? 

-- 
Realos