I am thinking of buying a tom tom sat nav kit. if it runs on 12 volt whats the best dropper to use.
No need to worry about a dropper as the charger supplied is 12/24 volt
The Tom Tom units run on 12 and 24 volt.
This is from the Tom Tom website, the section that describes what is in the box for each unit.
Cigarette lighter cable, with 12-24V cigarette lighter adapter which can also be used in trucks. This is the normal way of providing power to TomTom GO when it’s in your vehicle.
esso are running a comp along with coco cola prize is tom tom 500
see coupon in garage
Just had a go with a sat nav today doing for the first time doing two deliveries in South London I knew both deliveries so I did not have a problem, I decided not to go down a 7’ width limit what the lady told me to do 
Taskman,
never mind the width limits, just swing a left or a right, in seconds you will be re-routed. Just wait until you try it on somewhere (especially in a large city) that you haven’t been to before, you will be hooked. Yes they make occaisional mistakes, but you don’t need to suddenly grab a map whilst driving to try and find another route when you can’t take the one you planned.
John
Taskman:
I decided not to go down a 7’ width limit what the lady told me to do
An old fashioned paper map would not have helped either as width restrictions are not marked on them either.
Ossie
Since trying one a few months ago and being very cynical before I did, I am now hooked.
I no longer carry a large box stuffed with maps around, just my Tomtom and a Truckers atlas for bridge heights. Sure every now and again the lovely Jane will try and send you down an unsuitable road but will soon get you back on track when you ignore her! 
If you are on general haulage, tramping etc and are going to new places every day they are worth every penny.
talking of pennys save a few at argos they have 20% off sat nav stuff at mo
I’ve been looking at the Tom Tom, can the speeds for a different class of road be set e.g.
M ways 56mph
A roads 40… ish 
Urban 30mph.
It will be my Christmas pressy, with delivery by Santa Express.
try asking TomTom where the A19 selby bypass is
yet another black hole in the maps
Peirre, that just adds to the fun!
Driving down the new bit of link road from the A38 towards Tamworth Services the other day had Jane going mad. Turn left, turn right, turn around, she wasn’t happy. 
spardo theres a reason why the a19 selby bypsss doesn’t come its classed as the A63 and appears on my map
Alix is correct. the A19 still runs through the centre of town and meets the A63 near hazlewoods. It is the A63 which has been diverted away from town.
And after spending ages learning to drive it my co-pilot 6 navigates it successfully. 
Chunky:
Peirre, that just adds to the fun!Driving down the new bit of link road from the A38 towards Tamworth Services the other day had Jane going mad. Turn left, turn right, turn around, she wasn’t happy.
I know what you mean I was driving along there today, shows on the screen as a void then she tries to get you to turn onto the overbridges
Still a superb bit of kit though, I’ll never go back to using maps. Mines a TomTom 5 running on a HP Ipaq PDA.
Calv
i think these sat nav’s are excellent ive just recently bought a navman and its great but the only thing is im on supermarket work at the moment and althought the address might be " king st " you will proberly find king st is on an arcade and the goods entrance is a couple of streets away… not the sat nav’s fault.
I keep thinking of asking santa for one, but then most of my addresses are building sites, and the addys aren’t on maps yet 
For the last week I have been using a ‘Navman’ that comes in at £170 from Halfords, and what do I think about it?. Well it is a nice toy to play with and it does give out good info, like , ETA, miles to go etc, etc,(aint got the book in front of me). But if you have any intentions that a SatNav kit of any price will replace your locker full of street guides it won’t take it from me, they are geared up for the motor car and any vehicle that does not come within any local weight and width limits because this bit of kit will send you down them. In saying that it does have its uses and personally I can’t wait for another play next week, .
I’m considering buying one of these cheap(ish) Navman ones.
Seeing as our work involves going down tight roads anyway and my lorry is pretty small (DAF LF with a 6M flat bed) I reckon it’d be pretty useful.
Only think stopping me is that I know I can manage without it and I don’t like the idea I’d be using it mainly for work.
I work for a firm that don’t even give us a phone in the cab and didn’t really want to fit radios to the lorries, dunno if I can justify shelling out for their benefit.
any satellite navigation system is gear towards cars there are none that thake weight limits in to account as no one will be responsible for the data as it changes to quickly and the calulation would take ages
as for leaveing the maps at home I do I only carry a london a2z and a country wide alas if you use the browse map facility then it can be used as a moving map though if you’ve got the 320 then I’m not sure it has this facility it tells you to turn left andtheres a weight limit don’t turn its only a driving aid if you turn down a weight lmt and you get done for it then the excuse the satnav told me to won’t cut it