Substance Painter 2020.1 (6.1.0) ships with Output Templates for Arnold using the aiStandard material.

Arnold Standard Shader (Arnold 5 and higher)

Substance Painter Export	Arnold AiStandardSurface
BaseColor	Base / Color
Roughness	Specular / Roughness
Metalness	Base / Metalness
Normal	(Maya) Geometry/ Bump Mapping / bump2d (Use as Tangent Space Normals) (3ds Max) Bitmap → Normal
Height	(Maya) Displacement Shader / displacement (3ds Max) Object modifier → Arnold Properties → Displacement → Use Map
Emissive	Emission/ Color (Emission Weight = 1.0)
Anisotropy Level (not included in default Arnold Output template)	(Maya) Coat/ Anisotropy (3ds Max) Coat/ Anisotropy
Anisotropy Level (not included in default Arnold Output template)	(Maya) Coat/ Rotation (3ds Max) Coat/ Rotation

Maps that represent data will need to be interpreted correctly. Please see the Color Management page for more information.