I recently bought SH 5 for $12 AT Amazon.
I felt the same way about SH 5 when I first bought it.
Now after adding the Mods i`m hooked and I don`t even want to play SH 4. Just being able to move around the sub is worth it.
You will get first rate help here from the molders and some A1 mods to choose from. If you can afford it get it from Amazon...don`t get it from Steam it will give you problems. Make sure you get the 1.2 fix from here before activating the mods.