In reply to Timmd: The major problem with the spray is the lack of uniformity you get. That said you can concentrate the spray on more vulnerable areas such as the shoulders. I always use wash-in now as I found the spray too much hassle.
Just make sure you wash it properly first. Some will say running you washing machine on a rinse wash first which I find completely pointless as every washing machine rinses after every wash anyway! just make sure the detergent tray is clean.