Dedicated Truck Satnav showdown- The big three!

Using a new tt 6250 at the moment,alongside my trusty snoop until I fully learn the new boys foibles and idiosyncrasies.Struggling to input postcodes on tt and would you adam n eve it,the bugger wont play ball ffs.A quick look on a tt forum reveals one disgruntled user not being able to use his tt because the device insists on a road name first,even though many roads don’t even have a name,especially it seems where the chap works in the rural areas of Welsh Wales.This is perturbing to say the least if correct.