Suggest me a cost effective SATA SSD?

Hi,

I've inherited a system with a pair of these:

Model Family:     Crucial/Micron Client SSDs
Device Model:     CT4000BX500SSD1
User Capacity:    4,000,787,030,016 bytes [4.00 TB]

Their write performance is terrible. Struggling to get 20MB/s sequential
write. Their TBW count is low so it's not an issue of excessive write
cycles. I've searched around and established they are just really bad
SSDs. They also don't support SMART self-tests, which seems like a
really cheap thing to do.

I'm further confident that the problem lies with these SSDs because
there is a pair of much better SSDs in there and they perform as I would
expect. However, the use case for this storage is for lower cost so it's
not an option to just buy more of those.

So, could anyone suggest a decent low end (consumer/prosumer market) SSD
model that is known to work well without terrible firmware bugs under
Linux, preferably with power loss protection? Low write endurance is
fine. Capacity of 4TB ideally.

Thanks,
Andy