I've read in some of the reviews of v3 of TomToms that already some roads are out of date

but overall I've found it pretty good, it's only once taken me down a road for about three miles that at the end was closed
But I'm still of the mind that TomTom's is better value. Being able to move it from car to car, plus the speed camera warning (otherwise I'll never be able to insure a Cooper S in the future - still working off a TT99) are the big selling points to me.
But as always (and here's a lot of the fun of MINI2) it comes down to personal choice, and you'll always get advice on all options before you make up your own mind