From what I've read here on rv.net, sawn through generator handles are usually ignored if the buyer thinks the price is good enough. Especially if someone sticks a stick of wood there and wraps the thing in duct tape so it isn't as obvious.
Here are my suggestions... just my random opinion, so take it for what you will:
1: If you have a pickup truck, consider a camper shell. Out of sight, out of mind.
2: Thin security cables are worthless, they can be snipped, piece by piece. I like a security chain (made out of high test metal, not the stuff you snip off at the hardware store.)
3: You can buy both handle reinforcing kits, and LowPro LockDown brackets for Honda eu2000i models.
4: For a padlock, Master is OK for some things, but go with Medeco, Abus, Abloy, or Sobo locks for good security. The price is definitely higher, but you get what you pay for.
5: Look at what you are securing the generator to. I've seen chains that put Navy anchor tethers to shame tied to stanchions that could be yanked out of a truck bed with some solid tugging. Even securing to a tree may not be good if someone decides to cut the tree down.
6: Insure it. Get a rider on a policy explicitly for the generator, regardless if it is sitting in a vehicle or away from it.