Yes, this. Price/GB is probably the most important metric to consider, since the other metrics are either impossible to know (e.g. new drive reliability), hardly differ between products (e.g. power usage), or aren't particularly relevant for long-term archiving (e.g. read/write throughput, random seek latency).

Though for archiving purposes, I would steer clear of SSD's. While the overall (claimed) reliability of SSD's is similar or better than HDD's, the failure mode is completely different: where HDD's tend to develop read errors over time which gives you enough warning to plan a replacement of the disk, the SSD's I've had just brick themselves after X time, which means the data loss is sudden and total, rather than gradual.