Yes, reptile couriers or animal couriers are very different from your average postie service. Most reputable animal couriers now have heated vans and offer water to their charges on long journeys. It works out cheapest to join them on 'set-runs' (regular monthly tours of the country) rather than an individual trip, to cut down on costs.
Now, I haven't used any personally yet. I've been lucky to arrange transport through snakey friends or have managed to convince new owners that the coffee and chat was worth the journey (never mind the snakes :P). But I have heard good things about a few select companies. Reputation of a service is pretty easy to check on forums like RFUK.
I went on a show trip with this company before and know the guys running it have a lot of experience - Animal Transport Services - HOME