well I ended up ordering the ocuk version of the corsair h60 for £37(got a few fans so will try those before ording new ones if the ons I have don't do a satisfactory job.
will that handle 5ghz or still out of reach? been told that 5.3ghz isn't do-able with that so will leave that for the future with watercooling.
Should be ok if you have 2 fans in push/pull, make sure you set them to draw cold air in from outside the case