Id say the m17s menu was a massive improvement over the m12 but but if most people are skipping one of the main new features in favour of using the trims i think thats a bit of a fail heh.
having been on sanwa since 2011 i took a big chance going back to futaba this year but bo regrets what so ever. I dont think most people could feel the latency difference if there is one, it would just come down to the physical feel in tour hands and how the pots feel. You can adjust both radios however you see fit. In my case the steering was bang perfect out of box and the throttle was different but im starting to like it more. Or my driving is reflecting it i guess. I like how you can customize the menu to have your most used settings right up front in the user menu and you can pretty much forget about everything else.
the screen is very easy to read even in the sun.

big reason i shyed away from the m17 was the 1s battery. Battery life with my mt44 was horrific on the 1s 3000mah. Where my futaba or any 2s tx will go weeks and weeks. I have the 2s life and ive only had to charge it once since early july racing every few weeks and tinkering at home.
As with any device ymmv. You cant really make a bad decision so just go for the one you get excited looking at/holding.