It depends on quite a lot of factors, like goal, budget, features, etc.

If U just wanna run for fun, not training etc, a simple sports watch with a stopwatch will do. This will enable U to keep the time ran on Ur favorite route, & if U run the same route everytime, U'll be able to tell whether U've improved simply by clocking a better time.

But if U wanna know how much effort U've put into Ur run, how much calories U've burned, if Ur training to achieve a specific goal, then U might wanna consider a watch with heart rate monitor feature. There are complicated ones, as well as simple ones. Well-known heart rate monitors like Polar, Timex, Mio, even Garmin, they have several models to suit different needs. Some models just display heart rate readouts. Some models allow U to set lower & upper limits so U can set Ur target training zone.

The ultimate ones of course have so many features that might not be that useful to casual runners (unless U have the budget, of course). These can record Ur workouts & allow U to analyze so many things. Some can also measure the distance U've run, some can also record mileage for particular shoes Ur using.

When I started running I just used a simple Timex 1440 sportswatch. After about a year, when I started entering races, I bought the Timex Fitness HRM. Now that I wanna go faster in races (plus the fact that the Timex is no longer reliable), I use Polar RS300x SD.

The device itself won't make U go faster. But the way U use it, U can train more effectively when U know how hard exactly Ur running. U can follow a training program & prevent from going too hard on easy days, too easy on hard days. U can learn to push Urself, discover the limits of Ur body. I can go on & on about this, but in the end, it depends on Ur running goal.

I think ccube uses Garmin, I think FR60 (right, ccube ?). Garmin Forerunner 405 also is am advanced model, uses GPS to measure distances.