After over 4 years I got my notebook refreshed and moved from a Latitude D630 (core2duo 2ghz, 3GB of ram, 80Gb disk) to a Latitude 6430u (core i7 2Ghz, 8GB of ram, 256GB SSD) Good luck hunting for the detailed specs of the 6430u on Dell’s site as depending on the way you enter you may or may not find it (but the accessories yes!)
It took me a while to move all the relevant data from the old machine to the new but it’s now a couple of days that I’m using exclusively the new system.

On the positive side is:
1) the good expansion options; most ultrabooks don’t have any so it’s an easy win and for a system that should last 4 years a relevant thing
2) the decrease in weight; it is not a champion when compared with the other ultrabooks on the market or my old personal ultra-portable (Acre 3810T) but for the business category is a nice improvement
3) a comfortable backlit keyboard

On the negative side is the temperature and, closely related to this, is the fan noise.
I’ve read reviews on the network that praise the low-level of noise, but this is not my case: it’s most of the time on and fairly audible in an home-office environment even when setting the max CPU speed to the minimum possible (30%) and the cooling strategy to passive.
The standard feet are very thin (likely to keep the total height under the design limit) so the underside space to get the air flowing is very limited, raising it on the back (where all the electronic lies) is not helping.
When running heavy workloads (I have to often times) the fan noise gets absolutely nerve-breaking.

I’ve made already two BIOS updates (the system arrived with A01 and now I have A03) hoping to get this more under control as happened with other notebooks in the past, but this did not happen.

In short: if you plan to use it in a place with a low noise floor look somewhere else or wait until the fan issue is under control. Maybe a core i3 will generate less heat, even if the TDP on the paper is the same, and make the fan kick in infrequently.
If you’re always using it in a noisy place (open space with other people, airports, etc) fan is less of an annoyance.

I have a single day trip planned soon and will share my experience with the battery life afterwards.

Anyone with a success story on managing the heat and noise of this notebook is welcome to comment with advises.