does anyone have any experience or knowledge of these please?
What were the dogs symptoms and how easily did the vet diagnose them ?

My book, Owner's Guide to Dog Health bu Lowell Ackerman (v good book, recommend it) says:

Clinical Signs:

Difficulty urinating (straining,pain)
Somtime urine passed that is cloudy or has blood in it.

Otherwise the dog appears healthy, normal temperature.

If stones are suspected, urinalysis (looking at urine under a microscope) is usually done to look for crystals.  X-rays can be taken to look for stones as well.