Rocket Ray

I am a newbie and I have a question about buying some struts and shocks from newtakeoff.com. I bought my car last summer, I only drive this car in the summer and plan on putting 4-6k miles on per year. I have a barn I store things in, and I have always been impressed on how well the oem stuff lasts. If I were to buy a set of replacement struts and shocks, would they last say, 10 years until I need them?. I am not too worried about the shocks, but are the struts gas charged, and would the gas leak out over that period of time?

I should say that I actually like the ride of the stock suspension, I am not going to race this car, it is plenty stiff for me. I would put my money into real leather seat covers before I would upgrade the suspension.