I have just about finished my first roller motor build up and have a question about break in time. Do I need to run the motor at 1500-2000 rpm for twenty minutes or so like a flat tappet cam break-in or just get it up to operating temp? Not sure about getting the rings seated. Any help would be appreciated, thanks.  

seating the rings will be the main consideration when you fire this engine up. a good coating of the lube that should have come with the cam will work for that part. the rings will depend more on the type of lube you used when you assembled and punched in the pistons.
i've had the best results using lighter oils on the rings like marvel's mystery oil or even transmission fluid. the heavier oils tend to keep the rings from seating until the temperature of the oil gets high enough to thin them out. chrome-moly rings will take the longest to seat due to their hardness and won't be completely sealed until you've been driving for a while.
give the engine a nice shot with a pre-luber right before you drop in the distributor and when it fires, adjust the idle screw up to 1500 rpm and start hovering around it checking for leaks and keeping  an eye on gauges. adjust the rpm's up and down every few minutes to help seat the rings and keep all the little particles from the initial break-in flushed out of the bearings. start dropping the rpm's slowly after the engine has been running at operating temp for a while till your at idle speed. now you can start tweaking your settings. cam break-in with a roller is minimal and the rings will have had a good start on seating.
this is usually when i start to notice all the looks i'm getting from the neighbors. i can't pass up the thrill of doing the fire-up with the headers uncapped. after all, this is your first reward for all the work it took to get here.  

"sds-oe" has added some great points but I guess I would sum it up by saying that break-in will have to be a lot less worrysome than a flat tappet's. Agreed, some initial run time will be best, it's a good time to change the oil while the engine is hot and try to get all the debris from buildup and bearing material, etcetera out. I believe that most of the ring seating will be done when there is some load on the engine, not just spinning in neutral.

P.S. Even though I'm being a little finicky, how can a moly ring take longer to seat than a chrome ring? A moly coating is much softer than a chrome one...  

Are there chrome rings,moly rings and chrome-moly rings?I thought you had cast,chrome-moly and steel?Learn me something!  

i've been living with a misconception for years. i always thought the rings in question were an alloy of chromium and molybdenum, not according to the hastings site i visited. look at: http://www.hastingsmfg.com/ServiceTips/ring_set_composition_recommendat.htm
it shows that the learning process never ends.