If you do install halogen lights, be very carefull to keep cumbustables far away. Do not use open halogen bulbs. Halogen may not be a good idea in the shop because wood dust is cumbustable. Just by looking I get the impression they make more heat than regular bulbs. Halogen bulbs get very hot and they draw a lot of power.
Florescent lights are very efficent and are perfect for the shop.
If you do install halogen lights, be very carefull to keep cumbustables far away. Do not use open halogen bulbs. Halogen may not be a good idea in the shop because wood dust is cumbustable.