I haven't had a chance to "touch" 7.903, so I can't say whether any changes were made to the ordering or content of the menus. But as I say - back everything up, and you can always backtrack if you need to. For what it's worth, all you need to do if you don't like the results is to copy back all of the loose files in the root directory of your backup folder back onto the root directory of your TomTom. That's where the application resides.
If you find that you're good with the newer release of firmware, and find that the maps for your area are indeed a sufficient improvement to justify the cost, then you can update to the new maps and enjoy some extra features that will come along with them. The routing will, for example, take known traffic data into account using your day of week and time of day. Apart from accidents and the like, that will get your arrival times a whole lot closer than those you've seen before.
I was using the new firmware a couple of weeks ago, and on a Sunday, zipping down the interstate through Denver a something (I won't say HOW much) over the speed limit with the other traffic, my TomTom refused to buy me back even an extra minute of my arrival time. Seems the TomTom KNOWS nobody ever does the speed limit on I-25 at 3:00pm on a Sunday afternoon!
