Both teams won their opening two Heineken Cup Pool 6 encounters and Robshaw is looking forward to getting back to European action.
"It's going to be pretty special," he said.
"They are the big guns you want to play against in rugby. You have really got to test yourself and find out what you are about.
"Everyone is really looking forward to it. We will enjoy tonight and rest up and look forward to it next week."
Harlequins' victory at the weekend was their 14th of the season and Robshaw had high praise for his squad.
"Our defence has been spot-on this year. We had a couple of lapses towards the end there, but the guys really fronted up today (Sunday)," he added.
"It was about the squad. Some guys came in, the likes of Tom Casson and Charlie Matthews, and did exceptionally, so we are very pleased with today's efforts."