Bahai is not a residential turf grass.....but granted, long ago, we mixed bahai in our bermuda seed mix b/c it germinated so quick (we were seeding large industrial & warehousing sites)
St. Aug vs Bermuda......my very simple take:
1. 2 totally different turf grass looks. St. Aug wide blade and rough texture appearance.....vs bermudas thin blade and fine textured appearance.
2. Bermuda easy to care for, and most fellas want there lawn short, so bermuda is best if you want to keep at a lower height (irrigation and feeding your lawn will be needed if keeping short.
3. Bermuda very easy to keep weed free.
4. I have St. Aug, and currently am at 4.5" inches on my mower deck, and will take to 5" w/in 2 weeks. When I finish cutting, it looks to be 2 inches, but when you step off in it, you will loose your shoe. allows far less water / irrigation consumption and if I miss a occurrence, it does not look shaggy, and at that height, I seem to resist drought better
5. I'm not picky with fertilizers and generally use any time release feeding
6. for both, I will hammer them with iron to get that deep green color (and it let's my neighborhood know that I am the ALPHA)
7. before you start pumping fertilizer to it, check the PH of your soil.....most lawns in central MS need lime to get the ph right. if your ph is off, fertilizer is almost a mute point
*MY 2 cents