You'd likely be just fine using that meter for DC circuits. Meters and test lights are handy to have but if you choose to only have one, pick a meter. The meter does much more than just letting you know there is voltage present. Like Gatecrasher, I've been using Fluke meters for years, but my job required something accurate so I could justify the price. In by spares bag for the bike I have a cheap (actually, free with coupon) Harbor Freight meter that will do fine if needed on the road or trail. The key is learning how to use it!
01 Jeep XJ w/ 200,000 miles as of 3-26-11