What I use right now:
Suunto Vector

* Altimeter: Altitude, vertical speed, altitude alarm, logbook, vertical difference measurement, automatic 24h altitude memory, temperature compensation. Logbook capacity 8 kB, recording intervals 20s, 1min, 10min and 60min, with respective times 10h, 12h, 7 days and 10 days
* Barometer: Sea level pressure, absolute pressure, pressure difference, pressure trend indicator, 4-day barometric memory, temperature
* Compass: Cardinal bearing, North-South arrow, bearing tracking, declination setting
* Chronograph: Stopwatch, countdown timer, calendar, three daily alarms
> Although there's something wrong with my motherboard, so I'm getting the Casio PRG-80 Titanium as my next purchase.
For quality and reliability, plus fashion(Hehe), I use a
Tag Heuer Kirium

Almost forgot about this one. I rarely use it nowadays.
Will be getting a
Casio Pro-Trek PRG-80

Functions
• Full Auto EL Backlight
Automatically deactivates the Auto EL backlight function when surrounding light is sufficient, and activates it under dim light or dark conditions.
• Low-Temperature Resistant
The timekeeping module is designed for operation at very low temperatures. The value indicates the lowest temperature at which the module will operate. *-10 °C resistance does not apply to the direction sensor.
• Solar Power
A solar cell provides power for operation.
• Duplex LCD
Two liquid crystal panels make it possible to select from among different display patterns.
• Compass
A built-in direction sensor detecs magnetic north.
• 10,000 m Altimeter
A pressure sensor detects changes in the air pressure and converts the result into an altitude up to 10,000 m.
• Height Gain
This function sums all the meters you have climbed. So that you can see at a glance the total ascent on a tour.
• Barometic Pressure Measurement
A built-in pressure sensor measures barometric pressure, which is shown on the display.
• Temperature Measurement
A built-in temperature sensor measures the temperature.
• World Time
Displays the current time in major cities and specific areas around the world.
• Stopwatch
Accurate measurement of elapsed time with the touch of a button. The fraction indicates the unit of measurement, while the time figure indicates the maximum time measurement.
• Timer
Counts down from a start time specified by you. The value indicates the number of timers available, while the time figure indicates the maximum starting time. R indicates Auto Repeat, which automatically restarts timing at the end of each countdown.
• Yacht Timer
The yacht timer is used to time the start of regattas. The countdown period can be set from 1 to 10 minutes. An accustic signal is ermitted after each minute has elaapsed and then once a second for the last ten seconds.
• 5 Daily Alarms
The daily alarm reminds you about recurring events with an acoustic signal at the time you have set. You can also activate hourly time signal that indicates each full hour. This model has 5 independent alarms for flexible reminders of important appointments.
• Battery Level Indicator
Indicator shows the current battery level.
• Full Auto Calendar
Allowances are made automatically for months of different lengths, in case date corrections for leap years are required.
• 12/24-hour Timekeeping
Times can be displayed in either a 12-hour or 24-hour format.
• Mineral Glass
Hard glass resists scratching.
• Resin Band
• Water Resistant
The M value indicates the number of depth meters to which water resistance is ensured. 100m means water resistance to 10 atmospheres.
• Accuracy
+/- 15 seconds per month
• Type of battery
CTL1616
• Dimensions
62,3mm x 52,2mm x 14,4mm (H x W x D)
• Weight
77 g