Hi unwashed, i have experience in high performance built up felt roofing which will last longer than 10 years if done correctly. I have in the past had to strip falt roofs that have been covered with rubber membranes, one in particular that I remember near didcot had only lasted 10 years and when the customer tried to contact the installer they had of course gone out of business. I haven't had experience of the epdm system so the case may be it might be very good and like you said you can do it yourself which will keep the cost down for you. As with anything in life there is pro's and con's to everything.
