As already mentioned by the other fellas, the benefit of SHR over RAID 1 is to utilize any "lost space" due to different capacity drives.
I don't have experience with recovering data from SHR technology, yet. So not 100% sure what the recovery would entail, though I would imagine SHR recovery should not be that much different than RAID 1. Perhaps SHR uses some special offsets, headers, etc. Now, for striped RAID configs, SHR config may be more complicated than traditional ones. I would expect they would have some proprietary stuff to allow for these on-the-fly expansions and RAID re-configurations without data loss.
You could potentially find out the difficulty in recovering it through testing while the drives are good. Configure the box as SHR, remove the drives and analyze.
In case of failure, as far as data recovery service cost goes, there are so many other factors involved as far as expertise, equipment and price pitch differences among data recovery service providers that making a decision on what lab to use based on cost is a poor approach.
If you ever need quality data recovery service at fair prices, then the providers here on the forum are excellent choices.