Derek,
Its quality not quantity yes they are worth a small % but if the company are going to sell those leads to every carpet cleaner in the area then the conversion rates arent going to be very good as Most will probably pick the cheapest, If however they are only selling them to only you and targeting doctors, Directors, Bently, Range Rover Audi owners then they are probably worth a £10 + a lead.
Im not against the idea and have just sent a cheque for £25.00 to a shop who reccommended me for a £250.00 job but they know i will only pay them once the work is carried out.
Paul