The German said having to cross over between tyres, from wets in the morning to slicks in the afternoon, helped him to get comfortable in all conditions in the VJM06.
"It was an interesting day with the conditions [and] the perfect day for me to practice," Sutil told reporters at Barcelona.
"We can expect probably to have those conditions in Australia and Malaysia.
"At the beginning with the wet, and then intermediates, and also the crossover to slicks was interesting.
"We made some good changes to the set-up in the rain, and in the dry the car felt good as well."
Despite missing out on a potential three days of testing, and also losing running time to the weather, Sutil says he has no concerns ahead of Melbourne.
"You can have more days and feel more and more comfortable," he said, "[but] our car feels good to drive so I already feel comfortable.
"[Tomorrow] we have some long runs planned, maybe some soft-tyre runs in the morning and then race simulations with pitstops in the afternoon.
"It's everything we need to do before I got to Australia."
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