I have a simple set of harbor freight metal car ramps that work just fine.
However they also make some plastic car ramps that are also great ramps.
Some good car ramps that are considered the best car ramps and have great reviews are.
RhinoGear RhinoRamps Vehicle Ramp.
Race Ramps RR-40 40” Race Ramp.
Nicky Nice Solid Steel Auto Ramp Set.
Magnum 1002-01 Automotive Ramp System.
Trailer-Aid Tandem Tire Changing Ramp.
Black Widow PSR295 Car Service Ramps.
Specter 08226 Plastic Automotive Ramp Set.
Car ramps are much safer than jack stands in most cases as the car ramps are more stable and hold the car up better and they cannot tip over like jack stands could.
However sometimes you need to remove the wheels from your vehicle and then you would need jack stands which when used properly are also safe.
It's a good idea to have both jack stands and car ramps because sometimes you'll need the jack stands and sometimes you'll need the car ramps.
Car ramps are safe to use for oil changes.
When using car ramps to raise your car up or vehicle up to change the oil make sure to set your parking brake or emergency brake and chock the wheels.
Put a wheel chock behind each of the rear wheels to avoid the possibility of the car or vehicle rolling back although the emergency brake or parking brake should hold.
You just never know and it's better to be safe than sorry.
Drive your car or vehicle up on a good set of car ramps and then put the vehicle in park and if it's a standard transmission put the transmission in reverse.
Put the parking brake on and chock the wheels and it should be very safe as long as the car ramps are in good conditions.