Courtois is more than familiar with Valdes’ abilities, having faced the former Barcelona number one on several occasions over the past three seasons while on loan at La Liga rivals Atletico Madrid, and does consider his counterpart an excellent shot-stopper.
However, when discussing how Real Madrid star Iker Casillas would fare in England at his height of 6ft 1in with Spanish radio station Onda Cero, the Belgian international extended the subject to include Valdes, who is a full inch shorter.
"It is a difficult question. Casillas has grown in Spain and switching to another league is not an easy job,” said Cortouis, who himself measures in at over 6ft 6in.
“For example, the Chelsea's goalkeeping coach doesn't want any keeper at Stamford Bridge shorter than 1.95m. That tells you a lot. Here in the set-pieces, in corners and fouls thy hit you a lot.
"But it depends. Maybe Victor Valdes and Casillas come here and play very well,” he continued. “When I was in La Liga, people used to told me the same, that if I came to the Premier League I would have problems in the aerial battles. But to be honest, I am now here and I feel great in the set-pieces situations."
There has been speculation that Valdes’ arrival at United could lead to the in-form David de Gea making a long-mooted switch to Real Madrid in the near future, but Courtois isn’t convinced that the man who he replaced between the posts at Atletico would want to leave Old Trafford.
"I think it is very difficult for De Gea to leave United to join Real Madrid,” he added. “He is an icon at Old Trafford and he used to play for [fierce rivals] Atletico Madrid. But of course he has the talent to play for Real Madrid."