Gunter is a pet acquired through

This page is up to date (v1.3.1).
Gunter
Error creating thumbnail: File missing
Pet ID: melvorF:Gunter
Source:
Error creating thumbnail: File missing
Runecrafting
Drop Chance: See: Acquiring Pets
Effect: +10% Chance to Preserve Resources in Runecrafting
Part of 100% Completion: Yes
Error creating thumbnail: File missing
Runecrafting

. The chance to preserve resources from Gunter is additive with other resource preservation bonuses, such as those from Runecrafting Mastery, Agility obstacles, Crown of Rhaelyx, Runecrafting Skillcape, Max Skillcape, and Cape of Completion.

There is no best item to runecraft to acquire Gunter, all items are equivalent.