I don't personally use Electrum, but I have never heard of any (serious) security issues.
About the signing, I can help you out there:
Signing with a bitcoin address and a PGP key are two completely different things.
Even though they use the same principal (Private/public) key.
Electrum can sign/verify bitcoin keys.
If you need signing/verifying of PGP keys, then will you need another application, e.g. Kleopatra.
Feel free to ask question, if any
Edit:
The public key of the OTC user Animazing can be found here:
http://pool.sks-keyservers.net:11371/pks/lookup?op=get&search=0x22453004695506FD