Central America - Is there any other full transit tours of Panama Canal besides Pacific Queen?

I am not looking for a ful blown cruise, but just a single/two day trip.
It seems that I can only find the Pacific Princess via Panama Marine Adventures. They only do the full transit once a month.
Any others out there? Is there a rule limiting tours to the 3rd Saturday of the month? That time frame is not working out for me.

We had a bad experience with Pacifc Queen last weekend, I cannot reccomend them. Granted, the canal was an experience not to be missed, but if you have another choice- take it.

We paid 115/person for the half transit, boarded a very nice A/C coach with about 20 others at the dock and were transported to Gamboa. There we found that we were the last passsengers brought to the boat. The boat was packed to the gills with a tour group (appeared to be from the Carribean or another Central or South American country.) They had brought what seemed to be all their hand luggage with them. There were roll aboards and duffel bags stacked on the decks. Every seat on the boat was either occupied or had someone's backpack or tote bag "reserving" it for them. After an hour standing on the various decks and peering through the crowds to see the sights, we finally got fed up and went to the a/c front of the lowest deck and just moved some bags and had a seat. Lunch was ok, our group was called to the buffet line first (by colored wristband) but I don't know what it was like by the time the last group was called. Did I mention that many members of the tour group were small gchildren who ran about the boat bumping into other passengers, yelling and just generally being rude? They appeared to have no interest in the canal at all.

There is an option for the first Saturday of the month that we are checking out: http://www.canalandbaytours.com/ingles/en-enlaces.php#

Seems like an okay tour.
Would love any advice on other Panama tours in general. Will post a trip report when I get back.

We ended up using the Canal and Bay Tours. The boat was about 45 minutes late leaving.
We booked it through My Friend Mario tours. Extra $5, but they picked us up. Was nice to have a direct ride to the boat, rather than using the C&B bus. Let us sleep in 30 extra minutes.
Great narrator. Food was decent and plentiful. Continental breakfast and full hot lunch. Beers available for $2.
Unless you are really into boating, seeing big ships, I would opt for the partial tour, but we enjoyed the full tour. The bus ride back was an adventure. Think the bus driver was his first time driving a bus.
A full tour is a long day. We got back about 8:30pm.

We used My Friend Mario for several tours and all airport transfers. Great service. The Embera Indian Village tour was a solo guide, who knew the tribe well. Made all the difference.

Unless you are really into boating, seeing big ships, I would opt for the partial tour, but we enjoyed the full tour.

Never take a Full-Tour ---- Always the partial. I've done the partial several several times...