I'm not so sure about that. From what I've seen he's similar in style to Stones, in terms of he's good on the ball etc. But a bit quicker, stronger, better in the air and hopefully less errors in him. I think Laporte and Otamendi will be the starting pair eventually. Stones form has been poor and it will take some time for Laporte to settle in, but in a 2 I think Laporte and Otamendi will be the preferred pairing
I personally think before John got injured he was head and shoulders above any one in the league. Since then otamendi has gone from strength to strength and really grew with the pressure on his back. I do however think right now Otamendi will be the main man but by the end of next year John and Aymeric will be the starting pair and by the time they are 28 will be the best centre back pairing in world football.