I'm a fellow no-thumber, and I prefer playing straight as well. Here is what I can tell you about the BTU. First of all, it took me a while to get along with this ball. Out of the box, I really didn't like it. It seemed allergic to oil, yet it actually came off the dry pretty darn hard. After doing some surface adjustments, I finally settled on a 500-grit surface. At that surface, I get it to read the lane a little bit up front (still not grabby by any means), and it offers a strong backend, but nothings as violent as I saw in the beginning.
In regard to the ball being better than urethane, I'm not so sure. It is different than urethane. It's definitely much cleaner up front and more powerful down the lane. However, I find that I have to play the right kind of shot to make the ball work. For me, I've had the most success playing tight lines up the lane on and making sure not to get it to the dry too quickly. If I do, it still tends to come off of the spot a bit harder than I'd care for in most instances.
Still, I do think that it could pair up nicely with a mix. I think the BTU would be nice for when you need a little less grab early and a little more pop late. Just be wary that if you're throwing no thumb, this ball WILL hook when it finds dry.