| Criteria | Rating | Commentary | | :--- | :--- | :--- | | | ⭐⭐⭐⭐⭐ | 30+ years of active support is unheard of in electronics. | | Backward Compatibility | ⭐⭐⭐⭐ | A 1995 card fits in a 2025 rack. Impressive, but rare. | | Technology (Speed) | ⭐⭐ | Slow sampling (limited to ~20 kHz). Modern MEMS sensors exceed this. | | Cybersecurity | ⭐⭐ | Air-gapped networks required. Do not connect legacy firmware to the internet. | | Total Cost of Ownership | ⭐⭐ | High. Cards cost $3k-$10k. Repair costs are fixed-price ($2k+) due to lack of third-party competition. | | Ease of Migration | ⭐ | There is no direct upgrade path. Replacing a 3500 requires rewiring marshalling cabinets. |
During this growth phase, the 3500 Series rapidly displaced older analog systems. Key characteristics of this phase included: bently nevada 3500 product life cycle