I have 2 WE based L119's , I also now have the DE N4 . There are pros and cons to both. Available upgrades for the N4/MWS are certainly plentiful. However it doesn't kick as hard or frankly feel as robust as the WE's . It's a nice platform though , hop adjustment is certainly quicker than the WE . Mine has had the usual barrel , hop ruber and nub replacement . My WE's have had the same , barrel , rubber and nub . Beyond that they are stock, I know some folk decry WE internals , but I'have never had a failure in either of them (or any of my other WE GBBRs) that wasn't down to user error. Thousands of rounds through them and the bolt locks are still working fine.
And most real steel furniture fits the WE, MWS I believe is a bit more selective.
Mine have run happily down to under 5 degrees with careful mag management , any colder than that and I'm not playing !
I honestly dont find anything in it in terms of range and accuracy betwenn the WEs and DE
Go with whichever you fancy, based on my experience you wont be dissapointed with either.