Our downstairs loo is very delicate and gets blocked easily due to a sharp turn in the pipe somewhere.
I was panic stricken last time it blocked up and overflowed onto the floor. Thought we'd have to dig up the patio. Couldnt use rods because of the sharp bend. But we bought a "drain snake" which is a very long flexible tube that you force into the pipe and although it took several attempts, it did unblock the pipes. I thoroughly recommend them.
Now I never use the quilted type loo roll, only one well known brand that disintegrates immediately it touches water. I treat my downstairs loo with kid gloves

Ariadne xx