About two years ago I wanted a GPS/HR combo. But, trying to save money, I opted for a Timex HR and figured I could just keep using GoogleEarth to map my runs. Dummy! The Timex HR function stopped working after about 6 months. Granted, I was in a tropical environment and sweating quite heavily, using it...mmmmm.....an average of 5 times a week for 45 minutes to 1.5 hours. Now, chest strap no worky.
So I bit the bullet and bought the Garmin 405 with HR, almost a year ago. LOVE IT. Got it refurbished on eBay too for a better price. The touch-style bezel can be a little wonky when you're real sweaty but not too bad. Also, if you're doing a type of exercise where you bend your hands back, you may touch the bezel inadvertently. Annoying when you're trying to specifically watch HR or time. Only other thing I don't like is that you can't watch your time AND your HR at the same time; it's either/or.
Bottom line....for an HR monitor I do not recommend Timex. If you're looking for GPS/HR combo I am happy with my Garmin 405.