Raid 10 of 8 drives or 2 SSDs in Raid 1 on sata II?

Question

RAID

Good day to all. I bought a faulty Dell 2900 server for experiments at a flea market for as much as 3000 rubles)) I restored the motherboard, plugged in a second power supply unit, installed RAM up to 24 gigabytes. And I decided to build a file server on it for a working network for 100 people (simultaneously 3-6 users). The server has a Dell PERC / 5i Raid controller and 2 baskets of 4 disks. The controller only supports SAS and SATA 2 (3Gbit/s) interfaces.
The essence of the question:
How best to organize data storage in terms of performance, reliability and operation?

1. Install 8 HDD 7200k 1 terabyte each and organize RAID 10 on them. The amount of usable space is 4 TB. (24,000 rubles).
2. Install 2 SSDs of 960 GB each on tlc memory in RAID 1. The amount of usable space is 960 GB. (18000 rubles)
3. Collect RAID 10 on 4 SAS HDD 15000k 450 GB each. The amount of usable space is 900 GB. (22000 rubles)

The main issue is that the sata 2 controller and ssd will not fully open anyway, and the resource on the memory tlc does not inspire confidence. In the long term, it is cheaper to replace one HDD than 1 ssd. Will I achieve comparable access and write speeds when using an HDD? Or is it better to collect everything on a SAS HDD?

Answer 1

It's just a file dump. Speed ​​is not critical, IOPS even more so.
Collect from all Raid-5, optionally with one hot-spare and that's it. For a file dump, the linear read / write speed may be more than sufficient, there will be 6-7 TB of usable space