@millie - mine was also only 1% chance of reduction of recurrence as well, but because my cancer was aggressive and is known to recur and even come back as Metastatic Cancer - I decided to try the AIs for at least a year & see how I went. I lasted 6 weeks on Letrozole, 6 months on Exemestane and am now on Arimidex (2 months so far.) My side effects from Arimidex is way less (so far) than the previous two mes - but Exemestane took 6 months to 'work up' to the same as Letrozole in 6 weeks.
My surgeon said he would respect my decision to go off it, if it was causing extreme discomfort - as quality of life IS a very important factor. Right now, I am also taking medicinal cannabis oil (with the knowledge of my Onc) that reduces my side effects, making it more bearable - so I will continue taking the meds for the time being, being checked again in 2 months by my Onc.
Having said that - some people have no side effects on Tamoxifen, Letrozole or Exemestane - everyone is different.
As @melclarity says - it is more about giving it your best shot in case of a recurrence, and you may beat yourself up if you hadn't given it a go.
I figure, even if I give it 1-2 years, it would be better then not taking it at all.
Good luck in your decision making xx