Sorry i should have made it a bit more clear,
We use the Texatherm machines and not the chemicals, some of the sites that we have done over the last couple of months are 21000 sq mts +, however we are governed on these jobs by a time scale factor, in that we have only 2 days to complete the task, that is equating to 500sq mts an hour. Due to the clients pricing structure and contractual agreements we go over the carpet once, any stains get a second pass and thats it, if the stain doesnt come out then it stays. This is a cheap appearance clean, this is where the solution no2 comes into play, because we are not allowing much dwell time, and the pricing of the job, then no2 has worked out the best solution, if the job is a more thorough clean and we have the time to do more of a proffesional job where results count then we use the Chemspecs Roto-Brite as this gives a more thourogh clean than no2, that is my opinion only of course and i am sure that many of you will have a different thought on the subject, which i am sure you will all share with us, however we have cleaned close to 300,000 sqmts of carpet using this system this year alone and for cost effectivness V quality over price this works for us.
regards Dave