Yes,
They were a combine of about seven disparate manufacturers prior to 1990. After reunification, the group split into its various constituent members with varying degrees of success. Piko is the largest of the post'90 group and has a good reputation for excellent rolling stock (their post '90 production is truly excellent) but this is not surprising. During the DDR years, the enthusiasts were encouraged to engage with Piko to produce the most 'wanted' vehicles and Piko had access to prototype information hence many of their '70 and '80 models were very accurate (though coaches were shortened for toy track curves). Piko's moulding technique was above average for the period.