It's a nice hotel, so let's break it down:
Parking: Tricky. We were only in the Nissan Micra. If you're in a biggger car or SUV, you might find it challenging.
Reception: We checked in on a Friday. Everything was fine. We were advised that the restaurant was full that night (large coach party of Swiss tourists) but Anthea was more than happy to recommend alternative dinner options. I believe the hotel restuarant is also closed on Sat/Sun evening for dinner.
Room: We went for the Privilege Room. Twice the size of a normal room but well worth the extra cost. Totally recommended for the extra space. Free mini bar/snacks included.
Bathroom: Modern and clean.
Breakfast: Meh. Basically cereals/cold cuts. We skipped it on our last day even though it was included in our room rate.
Location: Excellent. Walk out the hotel door and look straight ahead for Europa Galleria. Walk 2mins up that road and your're in the centre of Saarbrücken. Left takes you towards the train station. Right takes you towards the main shopping mile. Great places to eat whichever direction you chose.
Special mention: Anthea Neuhaus. She checked us in professionally and politely. She then had to deal with me continuously forgetting my key card every time I came down from the room to smoke outside, and issuing me with duplicates. I think when we checked out I handed over six key cards. Every embarrassing for me, but Anthea was a star and a credit to Mercure hotels.
Nice hotel, great receptionist.