If you only go with the 200 lumen light, single mode is okay. I am going to say look at the P7 lights as well. Deal Extreme has a 2 mode MTE SSC P7 that is under $40. A charger and a pair of blue trustfire 18650 batteries will bring your total to around $60.
The light output on high is amazing and the low mode would be great for walking, etc.
http://www.dealextreme.com/details.dx/sku.12623
http://www.dealextreme.com/details.dx/sku.5790
http://www.dealextreme.com/details.dx/sku.4151