I don't know if I'll be much of a help or not, but thought I'd just share my recent experience in case it helps. We're heading to Maui in early April for a short trip (6 days), which gives us only 4 dive days. Although my DH and I feel that the perfect dive vacation is done from a liveaboard, we don't tend to dive more than 2 tanks a day while doing a land based vacation (like Maui). When doing land-based trips, we usually dive in the morning (shore or boat) then hang out and do other things in the afternoons.
With that in mind, I was all set to book us with B&B for our upcoming trip for 2 charters to Molokini (we'll dive with Lahaina Divers for 2 Lanai charters). After doing more reading and thinking, and knowing we only have 4 dive days, I started leaning toward booking Ed Robinson's 3-tank Adventure dive. Then TS&M posted they had dove with Ed Robinson's and after a private PM, we decided the 3-tank Ed Robinson's dive was what we wanted to do to get the most diving on this trip. Granted, if we get a really nice day where the trades aren't picking up too much, we may pick up a tank and spend 90 minutes diving Black Rock in the afternoon (since we stay in Kaanapali), but that's not for sure.
We'll be back on Maui in December for 10 days and that trip will be planned entirely differently as we'll blend boat charters and shore diving for our daily fix. Thinking of doing Rescue while we're there too, but we haven't decided for sure on that yet.
Bottom line for us was that if we're going to drive to Kihei to dive, we might as well do 3-tanks instead of 2. Both B&B and Ed Robinson's get consistently excellent reviews, both run 12-pack boats, both are eco-aware, and both try to split up their groups based on the experience and interests of the divers. Frankly, I don't see how you can go wrong with either of them. One big advantage that B&B does have over ER is that their charter price is cheaper.....they're charging $109 vs. $120 (plus tax). Based on that alone, I'd say book B&B.
