I would politely disagree with poshgravie. Put it this way...
You are part time, lets say 2 days per week as an example.
100 days per year use
£100 more is the slx than the clx (why is Yoda coming to mind?). Lets say it lasts only 2 years (it won't, it will last a lot longer).
£100 over 200 days = 50p per day more than the clx.
Will the slx earn you this 50p back...yes, you will work a little quicker as it is lighter and more rigid thus a little easier to control, you should be able to do a little more in the day, certainly enough to cover the 50p! You will also use less energy to do the same amount of work as you would have with the clx thus maybe being able to do a little extra work or be less tired in the evening. Your shoulders etc will appreciate the slx!
It's a no brainer for me, most things that make the time on the glass that bit easier are usually worth the investment as they cover there initial cost multiple times during their life.
