I haven't tried it biking, but the problem is not in sunlight but when you go out of sunlight. In sunlight it works like a champ and you can see everything nice and clear and at night the screen is dimmer than the HCX but no problem at night as well. The problem is during the day and you are not in direct sunlight (when biking in the woods with no direct sunlight) the screen is very hard to see, it is kinda of like a lcd watch. I hate to say it but the best way to explain it is to look at a display in the store, I don't know a good way to explain this. I think if you way in all the pros and cons, it really isn't a bad GPS altogether, I have upgraded the firmware lately with Garmin and it has fixed some issues, I noticed at first with the firmware it was taking a lot longer to get a fix and was concerned and after continuously using it, it has gone back to locking on fast. I'm not sure if the hot fix takes the last few fixes to get a baseline or what but it is working fine. I had saw a lot of negative posts on REI.com about power issues and failures of a few units and I had no issues of that with mine. I know the firmware had addressed the problems they were talking about and Garmin has always been good with firmware so I think that problem has been resolved. Now if some of these guys were updating their firmware and stopped the process in the middle it might have bricked their unit. I think if you buy one at a good company that you can take it back if you are not happy with it would be your best bet. I actually like mine better than my HCX Vista now that I am use to it and I use mine everyday a lot. I use it going to work and leave it running while driving around and carry it in my cargo pocket. If you look at the capabilities of this unit, they are much better than the HCX for overall. I'm happy with mine so far, I don't think you will go wrong with this unit or the HCX but you will have to make sure you can deal with the screen brightness. That can be a deal killer if you can't see it in deep canopy in the daylight. Just try one out and return it if it doesn't work for you.