I would deffo use it without a second thought and I would also pay a yearly fee or what ever as I feel that I am pretty competent in the home mechanic deparment its just that when you, and say your wife both use your cars daily for comuting ect it can be very tricky trying to sort out the simplest of things like servicing ect and just for ease I book them in at a garage to have it done, wich turns a job from just £40 in parts to £80 in parts and labour! when you are talking about 3 cars in your house hold that get seviced twice a year, the money soon mounts up!
Its also some of the simpler jobs that turn into a pain in the arse but when you have a roof over your head, lights, a ramp and tools that you can use untill the small hours of the morning without worry, It tends to help. It would be just like a self service garage thats open 24 hours a day.
But having about £7000 in hand tools and tool boxs ect I would be very concerned on people that had access to the stuff! It may not be the lads that pay to use the place it could be there freinds that they have taken along for company or whatever!