I agree that the graveyard is a bit... unfortunately timed given GWs release of the Garden of Morr. The GW one doesn't look any worse, even if it is a bit smaller. The only advantage of the Tabletop World terrain is that it looks more like a graveyard and less like a Necroplis or collection of Mausoleums (it actually has headstones).
That being said, I own the Guard Tower and it's a great kit. It assembles very easily and looks great on the tabletop. It's a great product and, in my opinion, well worth the price. Still, it's a personal decision. Just like some people don't understand why people pay excessive amounts of money for figures from Forge World, some don't understand the draw of really good looking terrain. To each their own.
I really wish they'd re-release the Ruined Coaching Inn, the Smithy, and/or the Abandoned Factory.