Yes, to sum up, you will be ok for the number of years you are talking about. However, (I hesitate to open up a new can of worms) I personally would lower the temp and rh some. You say 70ish for temp. Generally a temp lower than 70 is desired to keep an outbreak of beetles from happening. That's why I would suggest lowering your temp some. 70ish implies it can be above or below 70. I would also suggest lowering your rh. I find that cigars will smoke better at a lower rh. 68 to 70% and I find that burn problems become more prevalent. There are people who think that cuban cigars need to be stored between 63 and 65% and non cuban cigars should be stored at a slightly higher rh, but I don't buy it. I find they are all the same in terms of how well they smoke regarding relative humidity.
There are many past threads that deal with these issues. You should do a search on some of these terms and you will find a wealth of information. I'm not trying to sound condescending, just suggesting some research. That's why we all came to these forums, to learn more about cigars.
Hope that helps!