This place has the best and the cheapest Greek food you will ever have, no contest.
The portions are MASSIVE compared to messini and Alexandros as well as cheaper, I can't remember exactly but gyros are between $4-$5 depending on the meat you choose (my favorite and personal recommendation is pork) and the Greek salad as well as Greek fries are $4 or less. The Gyros are huge and the meat is fresh, not that sausage blend gyro crap that some places serve, this is fresh, real meat on a spit that you can see rotating behind the counter. The gyros are stuffed with massive amounts of meat, onion, lettuce and even french fries. Its warm and everything and delicious beyond description.
The greek fries are similar in size and in quality.
I have been to Alexandros and messini and they don't even come close to the food at Louis meat market, by far the best gyros on the danforth.
Edit: I was in here, stayed after closing time to watch the president's address live right after they shot Bin laden. History happens here.