RAID is a great thought for outside enclosing but it is not the better for all situations.actully many people simply require a big enough, fast plenty external enclosure that is also stable enough to be comparatively portable. To this market segment adding RAID quality is simply a sincerity accessory which adds to the cost
When you contribute in a RAID controller the cost has to be higher than a comparable planned non-RAID enclosure. The simply time this will not be actual is if you are equating different producers products and then as the old saying goes you acquire what you pay for.
To further separate this so soon niche market, many consumers do not need to purchase an all in one or plug and play device which arrives with its personal hard drives they want simply an empty enclosing so that they can select their personal hard drive as their budget and choice prescribes.
To even further separate this so soon niche market into yet a smaller niche, not all users are concerned in individual bay enclosures. possibly they like the idea of having two big and fast hard drives in one box, perhaps they program on doing a poor man's RAID and easy copy all from one hard drive to the other simply in case a drive fails either way they require a product which contents value for their money
If you believe that this must be one cripes of small market niche you would be wrong. As it is a niche of a niche, itís a firkiní vast market to start with and a little slice of a big pie is still a big old slice of profit to the company who is leaving to listen to their customers.