Leave it to you, Lisa, to bring the conversation back around to a salient point and actually draw a comparison that might prove helpful to people
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I haven't read the last 2 pages of this thread yet, so this may be redundant, but since there has been little to no comments on Blue XT Sea to this point (my point of reading), I thought I would mention the following, by way of comparisons:
1. Blue XT Sea departs and returns from/to downtown from the same pier as Aldora (usually referred to as the Aldora Pier). This is about a 3 block walk from Casa Mexicana. Call it 5-6 minutes, leisurely.
2. Departure times are 8am for Blue XT Sea.
3. Like 3P's, you do not have to surface as a group at the end of the dive. If you are the one in the group that is low on air, you can indicate that to the DM and he will shoot his surface marker buoy and you can follow it up to safety stop depth and then surface next to it where the boat will be there for you. If you are good on air, you can continue diving with the DM and any others in the group and surface later. We usually average 70-75 minutes on AL 80's. AL 100's are available for a $5 upcharge.
4. Based on everyone else's comments on how well Aldora does at grouping together similar experience levels and air consumption, I am going to give them the benefit of the doubt and just assume that my personal experience was an anomaly or outlier. I really mean that and don't want to offend anyone.
I communicated quite clearly ahead of time the experience level of me and my dive buddy (an instructor with similar experience on Cozumel and worldwide). I communicated that due to the cost premium we were paying for those high capacity tanks and that we were only doing 2 dives that day, we anticipated being grouped with similar experienced divers on the boat, given that surfacing as a group was our only option.
We showed up promptly at 7:30am at the Aldora Pier. The boat then cruised up north to the Aldora Villas to pick up our dive companions for the morning. We then cruised back south and right past where we were picked up 25 minutes earlier and then to our dive sites down south. During the cruise down south, I engaged our other 4 dive companions in conversation.
I learned that this lovely family, (Mom, Dad and 2 teenage boys), were vacation divers with limited experience and this morning was going to be their first time diving in 2 years and that they had some apprehensions and anxieties. After my talk with them and helping them sort out some gear issues, I made my way over to our dive guide. Confident that I was out of ear shot of anyone, I let our dive guide know about my conversation with the family and wanted to give her a heads up.
I was cavalierly told not to worry about it. We ended up having 2 enjoyable, but very short, 40 minute dives that morning. All 4 of the family members had issues throughout the two dives. No need to discuss here.
5. Blue XT Sea also
doesn't handle wetsuits- so, if that is an issue, definitely factor it in.
6. If cost is an issue or factor, definitely read the fine print and ask questions about whether the daily marine park fee, and the 16% government tax is included or not in your price quote for diving. Not to mention larger tanks and nitrox- it can all add up.