lolwut? Why would you ever treat an SSD as read-only? They are so much faster than mechnanical hard drives!
Any particular reason you need more than 100MB/s write throughput? Perhaps backups, but this applies only if you have multiple SSD's, since backup speed will be bounded by the slowest hard drive. Screen recording comes to mind, but your SSD will quickly run out of space if you do that, and that hits it pretty hard (not too much of a problem now, though). I really haven't got a need for very fast write (or read, for that matter) speeds. Low software latency and high IOPS is much more relevant to me and my SSD takes care of that very well, as all my executable stuff and operating system is on it.
PS: I didn't say strictly read-only, just that I wouldn't go writing gigabytes upon gigabytes of data on it every day. Mainly because I don't have a need for it, really (write limits are not relevant anymore).