I'm fairly new to the X10mil, but from the 2 days I have been using it I can say that it is a good piece of equipment that works to my satisfaction. It is quite possible that you have a dud that needs to be replaced. Here are few pointers that may help resolve some of the issues:
1.
GPS - when I got the watch I configured it and then started
GPS, set it on my table outside of my house and let it there for about 15 minutes. This establishes the initial synch with satellites in the area and assures that after the next start the watch gets reception in 30 seconds to 1 minutes. This has been the same for Polar G3 and also Garmin 405. Manufacturers recommend to do this every time you travel more than couple hundred miles from your original location.
2.
GPS fix on subsequent starts - it seems to help to by in the open for the
GPS acquisition after the start. I got signal in about 30 seconds this morning before the test run. Best to do this in a parking lot of as open area as possible.
3. As for the display - it seems to work for me. But I have seen many folks complain about the black display. Some even moved to non-mil version that is easier to read. If you can look at the positive display and try to change to it, maybe it will work better for you.
4. Alarm volume - never had issues to wake up to
Suunto alarm - I own T6c and
X10 and they both have similar volume of the alarm. I found Polar louder, but
Suunto seems to work well for me - especially if I set three alarms in the row ;-).
It seems that
Suunto has some production issues with some batches. I'm only wondering when my watch starts to peel. Oh we will see.
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 | Suunto X10 |  | Suunto commemorates 10 years with the Suunto X10. When you're trekking through a new frontier, adventure racing, biking, fishing, or conducting field operations, the Suunto X10 provides critical decision-making data. With full GPS functionality, including route planning and uploading, as well as outdoor essentials like an altimeter, barometer, and compass, the Suunto X10 wristop computer shows nature who's boss. | |  |
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