This add-on is really nice. If you are looking for a small route that contains some new locos and wagons, with great sceanry, look no further. Falmouth Branch is an excellent route. I never use the scenarios included with these packs, so I can't judge whether they work 100% or not, however, from using Free Roam, the route is great.
The locos it includes are:
Hall Class - Great loco. One of the older RSC Hall models from their old Hall pack, still sounds great and looks good.
0-4-0ST Shunter - These guys are awesome. Originally RSC had a Saddletank pack which included a bunch of these guys, unfortunately the only way to get these engines are from this pack or the Isle of Wight. It includes blocks as buffers (forgot the correct term), but if you own another of these 0-4-0 locos you can change the model and have proper buffers if you wish.
Pannier Tank - Haven't used this loco very much, however in the few times I did use it, it sounded and looked great. The sounds seemed very similar to the Hall, having lots of the same features.
The question, is it worth $30? No. Not by a long shot. I don't think any Railworks DLC that has been produced actually is worth their value. Especially the routes. If you wait for the Steam sales, like I did, $9 (currently) is a fantastic price for this add-on.