Surface pro 4 vs pro 9 July 8, 2019 16 32 64 128 Surface go 4 vs pro 9 Galaxy book 4 pro vs surface pro 9 Surface pro 4 vs surface pro 9 specs Surface laptop 4 vs pro 9 Surface pro 9 vs galaxy book 4 pro 360 Surface pro 4 vs Surface pro 4 vs surface pro 6 Microsoft surface pro 4 vs 3 Surface pro 9 pro 8 Surface 9 pro vs ipad