I didn't bother with a type 2 to type 1 cable either. As it turns out, I would never had chance to use it, but I use the Ecotricity chargers when there is one on my route, maybe twice to three times a month. I figure with the electricity I have drawn from the fast charger, I have saved approx £17 in electricity costs (compared with home charging) - when you calculate the fuel saving from the 18 - 20 miles it gives you at 80% SOC, that's about 420 miles or 10.5 gallons of fuel (at an average of 40 mpg). Total saving is therefore about 50 quid so far.
That is for a free card with free electricity, I think if it cost me anything for the charge or the cable - it would not be worth it. I have probably spent more than I have saved in Costa Coffee, but I like to keep up my lifetime mpg! - which is currently 87.7 petrol, 68.1 combined. Pleased with that!