Life expectancy of coolant hoses?

[Chrisn]

I have been reading up on all of the recent and very informative threads regarding the cooling system and low temp t-stat and am planning to put one in my 99 boxster this winter along with the S oil cooler. However, since the vehicle is now 10 years old, I just realized that I still have the original hoses (they still look good - outside at least) and coolant in the vehicle. Therefore, I am curious to hear what the opinions are regarding the life expectancy of the coolant hoses as I am now a little concerned that age and the 100 plus degrees in Phoenix may stress them and cause them to fail.

Thanks,
Chris