Yes, there are and I favor the WEM set. I have used both.
The WEM set offers a lot of PE for building the "covered wagon" version of the fairwater using their Conning Tower Frame Assembly. SJ, SD, and SV radar antennas are very well done with Early and Late options. You also get a Propeller Guard Assembly for building up the temporary prop guards used in the yards on boats that didn't have prop guards installed. WEM's accuracy and instructions are very good. Parts count = 52
On the otherhand the Nautilus package seems to be scale-up set of the PE they offered for Revell's Lionfish. Mostly railings, gun sights, simple radar antennas that are not accurate. I tried to use the 1/192 package on the Lionfish and the railings didn't fit. Parts count = 31
I highly recommend the WEM set. They have done their homework.
Qualified in Submarines 1965
"D..n the pressure, Six-Zero feet!"
"Most men would rather die than think, Most of them do!" - Bertrand Russell
"Boomers hide with Pride"