Bilt Hamber Autoclay. Soft or Regular?

[Parabola]

Am going to give my Alfa a good days wash next weekend.
Have decided to buy a Bilt Hamber Clay Bar. Like the fact I can use water as lube.
Was going to just buy the regular bar but a couple of people have recommended the softer version.

Any views or experiences? Many Thanks

[Parabola]

Should probably have mentioned. The car is black and very dirty.
It's covered in tree sap which doesn't shift with a normal wash!

Ta.

[Parabola]

Soft it is then!

Edited by Parabola on Monday 12th October 18:19