Well i use an empty USB, unless the virus can put itself there without i detecting it its very unlikely.Also reformatting it after every use, just for safety.
USB may contain MBR viruses even after formatting.
Also you can use a different CD every time you use it and burn it the offline tranasaction file to it.
That would cost you a good amount if you continue it for a long time. You could buy a Ledger or even Trezor instead of buying CD everytime you send BTC.
The QR Code looks nice , but then again the risk is that it can have a backdoor and put more info in that qr code than needed...
Hank is a known person and he created android litecoin wallet which is widely used litecoin wallet. He has also created a few other things such as litcoinj and feathercoin wallet. So if he really want to put a backdoor, he could have put in that wallets.
However, it is good to check more about that program by checking the code(if you know the language) or by checking reviews from trusted persons(least recommended).