This was one of the cheapest scarifiers/lawnrakes I could find, so was initially a bit dubious, but good reviews here reassured me and I ordered it. It arrived promptly and requires minimal assembly. The item comes with interchangeable scarifiying (solid blade) and rake (spring tine) blade drums. I used the scarifying blade on my lawns and completely filled a green wheelie bin with moss and thatch from under 25 square metres of lawn. The lawn did look somewhat thin in places after treatment, but now 3 weeks later, has regrown very nicely. The scarifier cuts grooves in the soil, which has aided re-seeding in a couple of bare patches.
I found this very easy to use. As stated in some other reviews, yes it does need emptying very frequently, but purely because of the sheer volume of debris it removes from the lawn. The collection net basket does have a fairly thin wire frame as mentioned in one of the poorer reviews, but it was amply up to the job IMO and I did not find it at all fiddly to fit. The only thing I haven't tried yet is changing the blade drum, but this looks like it is very quick and easy and the spare drum comes with what look like very good quality bearings, and is well made, so I am expecting many years use from it. Overall, very pleased indeed with it - far superior to an old black and decker lawnrake i had borrowed before.