Although not part of the published canon, I was just reading the essay on The Istari in Unfinished Tales last night, and it mentions that Saruman was aware of Cirdan’s gift to Gandalf, and that Saruman had a smoldering resentment of Gandalf, in part because of this. So if you want to accept that as how JRRT intended it, Saruman would have been fully aware that any ring he flashed around Gandalf would be seen as obviously inferior to Narya.
Originally Posted by AccessDenied
I tend to think that Saruman has simply ‘gone off the deep end’, calling himself “Saruman the Wise, Saruman Ring-Maker, Saruman of Many Colours!” He seems deluded and misguided by his thirst for power, such that he would attempt any ring-making at all. I do not think this was a token gift from Sauron, as otherwise he would have kept it hidden from Gandalf as he tried to convice Gandalf to join him, and also he would not have proclaimed himself as a ring-maker if he was merely a ring-receiver.
"I do not love the bright sword for its sharpness, nor the arrow for its swiftness, nor the warrior for his glory. I love only that which they defend," Faramir in TTT by JRRT.