Good spot Steve. I'll wait for someone else to TOFTT...
As for charges, this place isn't cheap, but the quality is usually high. £100 for 30 mins, includes OWO (I think it used to be 80 +20 for OWO, but they've made it std now). CIM, if available is +20. So, 120 for 30 mins with CIM - that's why I only go occasionally.
H