It's a good questions if electrum is safe, so far I've never heard of any instances of anyone losing anything with electrum. Of course it's open to the same risks as the qt wallet such as key logging and malware.
"I've never heard of any instances of anyone losing anything with electrum" - that's a pretty good recommendation then ....
Any computer connected to the Internet is at risk of being infected with something. That's why ultimately coins should be stored offline.
But if you are asking what's a good client for "day to day" use, electrum is your answer.
Agreed. Electrum is good for "day to day" use. If you want to have much money in BTC, store them on offline hard drive (just put file there and disconnect hard drive from PC). Sadly, there's no way to speed-up synchro in Btc-qt on Windows (only on OSX its possible). If you want to use wallet still connected to net, look on blockchain.info
Regards.