Stabilizer

Just bought a 2001 Toyota Avensis Estate which will need a tow bar fitted.

Also bought a secondhand ABI Dalesman 420/2 which the present owner uses with a stabiliser which he has offered to me included in the purchase price.

I have towed on and off for years and never needed (or felt I needed) a stabiliser, even with bigger caravans than this one.

What benefits are there and would I REALLY need it? I will always keep the weight well within its limits and load it correctly.

Thanks for your opinions and experiences.