Not judging you at all. I only use credit cards for the security and convenience they provide. I pay them off at the end of every month. The only things I buy on credit are homes and cars.
The light is a critical component in low/no light to identify your target and fire accurate shots. These will help save your live by shortening the OODA loop for you and increasing it for your attacker. It will also aid in reducing the danger to others from errant shots. These are significat contributions to your defensive plan and should carry some thought and a reasonable expenditure of funds.
I am somewhat of a gear snob. I like stuff that's ergronomic and reliable. These two attributes usually cost more money. Not always, but usually. The suggestions made by mhphoto are all good choices, with Surefire being the best. That's not because they cost more, but because they have a proven track record that is larger than all the others combined.
In the end, I hope you get a light that satisfies you AND your intended mission, with reliable results. Good luck!
