I had a double dirt bike carrier, I transported two KTM 525EXC's, about $275lbs each.
I did this with a Suburban with air assist rear shocks.
There is no way I'd put 450lbs hanging off the back of a Rav4. Whether the hitch can take it, the front of the RAV4 is just too light and the wheelbase too short.
It's not just a matter of whether the hitch can take the weight, it's a matter of keeping the front wheels firmly on the ground for steering and braking.
The trailer in a bag would be my choice it I had minimal storage space, that'll actually take up less space than the bike carrier when not on the vehicle.
I'm also a scuba driver and even with tanks and 30lbs of lead weights, my gear is no where near 450lbs. I can carry all my gear and a tank from the trunk of my car to a boat, I couldn't carry a motorcycle.