Side-by-side spec and price comparison. Live data from Amazon US.
Seagate Enterprise Capacity 4TB SAS 12G 512n balances price ($37.53/TB), warranty (5 years), and 550TB/yr workload rating for the best overall value.
HGST 4TB offers better value at $20.00/TB vs $37.53/TB - a 47% price difference. Factor in warranty length and workload rating when the price gap is small.
Mixing drives of different models in RAID is not recommended even if capacities match. Different firmware, error handling and seek patterns can cause rebuild issues. Use identical drives within the same RAID group for reliable operation.
Seagate Enterprise carries a longer 5-year warranty vs unknown years for HGST 4TB. Both are enterprise-grade drives built for 24/7 operation.
HGST 4TB is the better fit for NAS storage. It uses CMR recording which is safe for all RAID levels. SAS interface requires a SAS HBA or SAS-capable NAS.