if you have to change your drive , please go with an ssd you won't regret it.
except if you need more than 2Tb of space, it will cost a lot more than a hdd.
the ssd goes 10x faster than an hdd, so everytime your computer makes disk access it goes 10x faster.
please be aware that all computers wait all day long for datas coming from the drive. except when they simulate or calculate.
but most of the time, all impression will be more speed.
if you come back to an hdd later, or on a fusion drive (hdd with small ssd cache) you immediately feel that it is slower.