I've got an 8 year old Topeak Panoram that has never given me a lick of trouble. It's even on its original battery. It has been rained, iced and snowed upon countless times with no issue, even though it wasn't touted as being "waterproof". It has a wide screen that shows distance, elapsed time and speed all at once so I don't have to switch screens. The numbers are very large and easy to read.(Tundra_Man)
If you plan to ride in cold weather (below freezing), wireless is not a good choice. Especially if your bike stays outside for any length of time. You will be changing batteries to the transmitter all the time.(Juha)
Waterproofing is not a problem.(stapfam)
I vote for going as simple as possible(Velo Dog)
So I 'll go for something that has a wide screen that is simple and shows everything at once. I get a wired one since it does not need too many batteries and works perfectly fine in every weather condition. And a water resistant is sufficient and I won't need a waterproof computer. I'll use my heart rate watch for other training functions. Perfect! Thank you for all the posts.