SSD absolutely the better choice in performance terms and longevity terms. The amount of HDDs I have replaced during my time in the data center is enormous. SSD certainly faster, much faster, got no moving parts and it's few steps ahead technology wise, so if you can afford it - go for it.
As the user above me said, health monitoring is something you MUST Do regardless if its HDD or SSD, if you can run health check on monthly basis or you have certain health control / monitoring tool installed, that's an important part of any hosted HDD/SSD/Storage. Simply said, if you can't afford losing your data and bring needless down times - don't take it easy, keep your storage always in check!