Munster gave clear notice of their Magners League title ambitions when they saw off defending champions Leinster 18-0 in Dublin last week and John admits it will take a huge effort from the Warriors to stop the Munster machine.
He told the Evening Times: "It doesn't get any harder than Munster at Thomond Park and the fact that this is opening night for them with their new stadium will mean they are psyched up.
"That means we will have to go out and play with a Test intensity. Munster are so full of internationals that you could say this is virtually an international team we are facing.
"They have Paul O'Connell, the Ireland captain in the back row and he runs the show for them. But on top of that Jerry Flannery, Donncha O'Callaghan, John Hayes and Denis Leamy are all seasoned internationals.
"We know we are in for the mother of all battles up front to recycle ball quickly and stop them slowing it down and strangling it. But after our win against Scarlets, confidence is high and with the game live on Setanta and in front of a sell-out crowd, we are all looking forward to playing on the big stage."
A disputed Thom Evans try gave the Warriors a 21-18 win in their final Magners fixture in Cork last season and John says the Glasgow pack have their work cut out to give the backs the quality ball they need.
John said: "Thom is in great try-scoring form and the two he got against Scarlets last Friday at Firhill were awesome. But really, the whole team played to their best against Scarlets and we are going to have to go up another notch against Munster."