HMMM, I have driven boats with the dual switches for both drives as well as the one for tabs one for drives. I like to be able to trim the drives independently. It seems even on the newest and nicest boat out there aftere a while of trimming and running the drives trim at different rates. So then you have to attemp to reach the dash switches to correct them. Same as with the one button being tabs. If you run in rougher water its even worse with a tab button and a drive button. Sometimes you want to run just one tab down a little than the other, again you need to reach the dash. Its really all personal comfort. You'll get a lot of feedback. I like both drives in the throttles on two switches. Just my choice of how I like to drive.