Currently I have a 3k rpm quad led fan and a 2.5k rpm svc fan. They give out about 32 cfm and 28 - 30 dBa. Is it good enough or should I go for a TMD 70mm fan? These fans don't seem as effective on the SK-7 as they did on the GC68. My mental noise threshold is about 30dBa, anything higher and I could crack. Thanks.