Last Sunday I went to check the oil level on my '03 R53, and the dip stick broke off as I was pulling it out of the tube

Lucky for me the broken end was outside the tube, and I was able to pull the rest of the dip stick completely out

The dip stick is a 1/8" dia. piece of fiberglass rod with a black coating of plastic/rubber material which I guess is to protect the fiberglass from the oil and heat. I found this black coating to be cracked in MANY places along the length of the dip stick, allowing engine oil to get to the fiberglass rod, which I suspect weakened it to the point of breaking. Anyone else ever had this happen ??? Good news is that Moss Mini has a BMW OEM dip stick in their inventory. I ordered one online Monday morning and got it on Tuesday. $27.80 damage including tax and shipping. Suggest everyone check their dip sticks for cracks.
Pull it out, bend/flex it and look for cracks along the length of it. If it were to break off inside the dip stick tube, it might be a real pain to remove the tube and make the repair. I was lucky

Might be a really good idea to have a look at those dip sticks before heading up to Moss this weekend, you may need a new one and not know it yet.