I've tried all different types of bike computers, and this, to me, was going to be the holy grail. Although the price is very high, it has a lot of functionality that I wanted. One really cool thing is that it gets coverage everywhere. I went to one place where my older eTrex never got coverage, and this worked flawlessly.

One downside is the heart rate monitor. Despite the fact that this device supports HRMs, it doesn't support the HRM standard, which means you need to buy the special Garmin-made HRM strap, which costs over double the price of other ones. You may ask Why, like I did, and the response is that this is a one of a kind device. Bad answer. The obvious one is "We want to make more money by marking the price up by 3000%!". Oh well, it is a neat device. 3 stars

Garmin, with the Edge 305 heart rate/cadence, has set the standard and literally eliminated the competition. The only thing the others can do at this point is to copy in attempt to duplicate. We have (2) with HR and CAD. Both have been used on the flats of Los Angeles County to the hills of Orange/San Diego County. The GPS has never failed to work. Actually nothing on the Edge 305 has failed to work with about 1000 miles on each. You can program the screen to display multiple items and with a glance see all of your desired information. I monitor Speed, Distance, Elapsed ride time, Time of day, HR, CAD and Calories. Heck, The Edge 305 is better than the bike! The training software is also outstanding.
The only negatives have nothing to do with actual computer performance and in my opinion include:
*Price-This toy aint cheap.
*Size-Relatively big for a bike computer, but very light.
*Battery-Our units both are safe from four (4) to six (6)
hours. 5 stars

Short battery life.
Hard to read display.
Display not well organized.
Good, but room for improvement. 3 stars

I recently purchased the Garmin Edge 305, w/cadence, plus I added the heart monitor a couple weeks later. I commute daily on my bike and I do 350 - 450 miles per week, with weekend centuries. This is a great tool for anyone who wants to have a better understanding of their effort and cadence. I have found very quickly that by focusing on my cadence and heart rate, I have improved my overall times and have become even more efficient on my bike. The ability to, customize the display, set up interval trainings, upload rides to the computer, analyze the ride as a whole or part and compare to other days is outstanding. I would recommend the Garmin to anyone who wants to become serious about cycling, get the most out of their time on the bike, and improve their performance. A little expensive but worth every cent. It has even helped me find my way home when I have gotten out in an area I am not as familiar with. Must have for anyone who really wants to track results, understand effort, maintain data and improve performance. One negative is the battery life is truly only about 6 -6.5 hours, so for the longer rides I have left my Cateye on my bike so I have some reference for speed, mileage etc... another is the unit will go to "sleep" if left for more than a couple of days, but by holding both the Mode and Reset button for 30 seconds it will "wake" the unit back up. Still awesome!!! Ride Strong!!! 5 stars

I returned to cycling after a 20-year hiatus last year. Being a dyed-in-the-wool sucker for gadgets, I had to get the Garmin 305 as my bike computer. Cyclist friends of mine made fun of its size, made fun of my desire to map my rides afterward, and generally mocked the device. I ignored them, and I'm glad I did.

The 305 has been a great training partner. Thanks to its data recording ability, I can really easily correlate perceived effort on a day's ride with my actual performance in terms of speed, heart rate, and cadence.

Setting up all of the sensors on the bike was relatively straighforward (though the combined wheelspeed and cadence sensor setup was somewhat novel), and the directions were clear. You charge the 305 through its USB port. It comes with a separate power supply so that you can either charge it from a wall outlet, or from the USB cable connected to your computer.

On the bike, the display is large and clear. I've found it readable in any of the lighting conditions in which I'd be willing to ride the bike. The interface is relatively easy to navigate, though a bit puzzling to set up. Garmin's origins in navigation show in a couple of funny places. One of them is the default data fields displayed on the device: your heading is shown by default in the five data field configuration that I prefer, but your heart rate isn't. I was able to reconfigure it to display the fields that I watned to see, but I found the choice surprising in a product that is ostensibly aimed at athletes.

In use, I found that the GPS reception was generally good even in tree-shaded areas, but the startup process can sometimes be irritatingly slow. Data reception for the heart rate and cadence sensors has been glitch free.

In terms of durability, I've banged the 305 around quite a bit and ridden it in conditions that left other electronics begging for mercy (don't ride in the driving rain without putting your mobile phone in a plastic bag). The 305 still performs like a champ thousands of miles later.

As a Mac user, I found the Mac support lame at first, but it has been steadily improving with Garmin's release of their Training Center software for the Mac, a Mac version of their Web Updater tool, and improvements they've made to Mac support [...]. It's still not perfect, but it's very useful.

The ultimate endorsement of the 305 is that I'll be replacing it soon. Garmin has announced their upcoming new generation of Edge cycling units, and the 705 looks too good to pass up. I'm hooked on the capabilities and insight that the 305 has given me, and I'm looking forward to even more with Garmin's next generation. 4 stars