Advice on possible setup, DTQWT

[caz]

So I'm thinking about doing the Troels Gavensen DTQWT, the single 12 inch woofer version. using a Single Kappalite 3012HO.

I'm wanting to get a gauge on how you think these will perform in general and also for my application.

1.Im looking for Music/HT speakers for a small apartment setup (tho i want to take these with me for years). Probably a area in the realm of 150square feet. Potentially an open ended room thats much bigger as apartments tend to blend the kitchen/living/dining. I Cant pin point this down exactly as I haven't chosen the apartment lol. My GF and I are still hunting.
2. I don't have the money to get a dedicated sub anytime soon. So I want to make sure the build will perform with adequate low end bass. Its a TQW design, but the drivers (including the woofer) aren't exactly renowned as superb low end monsters from my understanding.