Dell laptops: The worst computer experience EVER!

Our office decided (to our supplier's suggestion) to replace our old laptops in the office with Dell laptops....and that's where our nightmare began. My new laptop was so slow that the supplier eventually decided to replace it with a "bigger spec" Dell laptop and obviously I had to pay for this on top of an already expensive laptop. The problems just continued and eventually I couldn't print or retrieve old emails etc etc and SLOW and hanging - eventually this started affecting our work in the office (we are 3 unfortunate owners of new Dell laptops in the office). Eventually the only conclusion we, our suppliers and IT specialists could reach was that Dell laptops have an issue with running Windows10 BUT Dell refuses to admit to this and they were just COMPLETELY not willing to help us - all they do is waste your time to run scans on your laptop so that they can say it's not their fault. WHOSE fault is it then????? The new desktop computers in our office have no problem with operating Windows10. Round and round in circles with Dell and NO solution. We have lost so many working hours and the stress this created in our office!! UNACCEPTABLE!! Our supplier is at their wits end and all they can say is they will never supply Dell laptops again but I'm still stuck with a defective Dell - STILL under warranty (which is worth NOTHING). I now know of at least 7 people in Johannesburg with new Dell laptops who have exactly the same problems with their Dell laptops.....but still Dell refuses to admit that it's their mistake. I've paid a lot of money for a thing (under warranty) that I won't be able to use. We are now forced to replace these Dells with a different brand at our own cost. BE WARNED! Do not buy new Dell laptops!!