Mercury suite is very easy to use, for qa, just create

defect, and put deions about defect, plus some document or image file, that is all.

for developer, he will be assigned the defect qa created, and work on it, when he finishes, he will use Mercury tool to close the defect.

the team lead will check the defects, assign to developer, check reopen, check closed etc.

SAP market share is about 20-30%, it is a company based in german; most for business data processing software, such as MDM, NetWeaver etc, SAP is the third software company in the world.