Good as always:

• High transparency of learning goals through consistent orientation towards gross enrollment rate
• Well-defined exam tasks for optimal preparation for C1 exams
• Current topics from everyday life, work, science and culture
• Intensive training for all skills
• Consistent work direction

The best I can be:

• Fully revised edition
• Update and linguistic editing of texts and topics
• Clear and fresh layout
• Improve vocabulary and writing training
• Systematic communication of strategies
• Intensive grammar instruction with many exercises