I start hot--400-450, all indirect to protect the meat--so that the fat side (always on the top) begins to melt and the meat and bones on the underside begin to brown nicely. After a minimum of about 20 minutes (if the meat was at room temperature) I reduce as low (170-225) as you can go (providing you have enough time) and let it slow roast---the longer the more uniform and tender the meat will be. You can also just lower to 325 degrees, as many recipes suggest, but this will give you a well done circumference and medium rare inside, rather than a seared exterior and perfect uniformity throughout.
