they would be quieter, however you are losing airflow also compared to the S-Flex. Tests may need to be done to prove that, but by the sheer specifications of each,

57.7cfm for the Typhoon and 28dBa 1850RPM

75 cfm for the S Flex and 35dBa 1900RPM

for sure 35dBa is noisy compared to 28dBa. the question is, the base difference in cfm is 17.7 cfm, so then the question becomes, what is the ACTUAL difference seen on the radiator; aka, how well do the fans perform