One thing to watch out for on the ELC bulbs is the nominal life. There are 50 hour and 500 hr bulbs. If you buy a long life bulb ELC/5, the light output is closer to the 80 watt ELB 15 hr bulb. This pdf from Ushio lists a number of bulbs and their light output and operating life.

http://www.ushio.com/files/catalog/pav-halogen-mr16.pdf