I know... it looks horrendous doesn't it!
Actually, it's held up on a 1-tonne SWL chain hoist, and 2 seperate ratchet straps hooked onto various different parts of the floor, and around the overhead I-beam. (which is probably good for 10tonnes) I'd say it's as safe as any other method of raising a vehicle.
Given my lack of a 2- or 4-post lift, this is the easiest and fastest way to gain access to the underside of the car! It's either this, or trolley jacks and axle stands, which are not ideal on a gravel/stone driveway.
The only thing this does do is utterly ruin the rear bumper... not that I care as it was knackered anyway.
Here's a rather damaged Pug 309 undergoing the same treatment:
