To be honest i'm happy with mine the way it is from factory. Not measured it but i think its similar to my other basses which are typically 18mm on the Warwick and Overwaters and 19mm on the Fenders. It doesn't make much of a difference when playing altho i did have an ESP 6 string with 16mm spacing and i kept getting my positioning wrong but maybe that was more down to the fact it was my 1st 6 stringer.
Dave