Just because your mates do it doesn't make it right. If they want to take the risk then that's their problem. You are asking us and three of us have said the same. This is not clear cut. There are two many factors pointing to a problem with IR35 and we have no idea what you know about it to be able to take your word that you are outside.
IMO you've two issues here. Your IR35 status is highly questionable. Get a contract check from QDOS for £99 to be sure.
Second is you don't actually know what the figures are. Calculators are highly inaccurate so you need to speak to an actual brolly to find out for sure.
Time to get on with both those tasks.