Liveaboard Sailing Classes
1. Are you going from "zero" to bareboat certified in one week?
If so, remember that you will be getting a crash course (pardon the pun). The skills and knowledge you come away with will depend greatly upon your level of pre-course book reading/preparation, your instructor, and your own aptitude and attitude.
2. If you will be learning a lot of new stuff, instead of just demonstrating your already-good skill set, then the setting may not be so important. After several hours of classroom-type lecture, then 4+ hours of sailing and drills, you might need to study another 2-3 hours each night. Will that leave time for really enjoying your surroundings?
3. FWIW, I took my most advanced training course in an ASA school, and the instructor just happened to be someone from whom I learned very little. Nothing against ASA, just an observation that the instructor can matter a LOT.
4. My opinion is that excellent instruction is very helpful, but the certification process is just a "license to learn." It will get you started where you have no other good options (learning from a trusted and accomplished sailor friend or relative). From there, you need to learn and practice good seamanship as best you can - on the water.
Best of luck to you.