Sorry, I'm having some trouble with the site today. I can't start new topics but I can now post.
Yea, Scott's weed killers aren't all that strong so you can apply and hardly notice there's weed killer down.
I have a product that I can get via the commercial side that's called "Viper" and it's bermuda-only product, but it awesome at cleaning up a lawn. I experimented with it last year on a new customer who had an awful bermuda lawn, tons of clover.
Two weeks after applying, it was completely clean.
The other problem you're having is the act of feeding and killing AT THE SAME TIME. So there's three types of products you can get - 1) that does a very good job at feeding and not so great at killing weeds, or 2) a product that does a great job at killing weeds and an ok job of feeding the lawn, or 3) a product that doesn't do either very well, such as Vigoro.
On the retail side, there's not a product for bermuda that does a real good job at killing weeds, items "2" in the above described list. But Scott's is definitely good at feeding. For relatively weed-free bermuda lawns, it's an awesome product. But if you have weeds, you better have a game plan for them separate from Scott's products.
For St Augustine folks, I do not recommend you use Scott's Bonus S, a weed/feed for St Augustine. Instead, go with Fertilome's St Augustine Weed/Feed. It's time release like Scott's, but with a higher grade of atrazine thus better weed killing and less danger to trees.