Ive been diving in the Caymans and many other Caribbean islands for close to 20 years and I find kimdave0s comments to be pretty much spot on.
Weather is a large factor and 90% of the time the winds are out of the east, creating high seas and turbulent conditions on the eastern side of the island. On a rare day, the diving on east end would be comparable to the north wall, but 90% of the time the north wall will be far calmer and generally better diving than east end. In fact, depending on the site its almost comparable to Little Cayman except the wall starts much deeper, around 60 feet. The west side is consistently calm although I found many of the sites to be over-dived, causing reef damage and artificially tame fish.
Ive read all the hype about Ocean Frontiers on several of the boards and thats why I gave them a try. Like the original poster, I was very much disappointed. I am not surprised to see the locals giving them high praise, since I am sure they receive special deals for doing so. A lot of the other rave reviews Ive read seem to come from people with timeshares in East End, promoting their on site dive shop and protecting their investment. But from someone with over a thousand logged dives and no dog in the race, Ocean Frontiers is an average operation at best, with fairly crowded boats to sites not any better than the north side and at significantly higher prices. Ive made the drive from Seven Mile Beach several times and its at least an hour each way during the week with all the commuter traffic. Last time I was there gas cost about $5/gal. so that was obviously a factor driving 40 miles round trip. With gas and tips factored in, my wife and I spent over $700.00 for three 2-tank dives with Ocean Frontiers. That is more than a 2 day package on Little Cayman, including lodging, food and airfare!
There is no significant difference in quality of diving between the north and east sides of the island, and I wholeheartedly agree that Bloody Bay Wall on Little Cayman is in a whole different league than anywhere on Grand Cayman. Ive stayed at Little Cayman Beach Resort, Pirates Point and Southern Cross Club. Of the three, I prefer Pirates Point, mostly because of their exceptionally good food, although they are by far the most expensive. Southern Cross Club has the best prices (except Mc Coys, a dump) and much better food than Little Cayman Beach Resort, which has the worst food and pretty high prices.
So here is my completely unbiased recommendations for the Caymans, based on over 1,000 dives, 200 or more of which in the Caymans
Grand Cayman:
Off the Wall or Wall to Wall, who I think may be affiliated. They charge $80 for a 2-tank and offer free transport to and from Seven Mile Beach. They go to the west, north and south sides of the island and take 8-10 people on boats the same size as Ocean Frontiers, who take more like 20+ people.
Neptunes, who take only 8 people but on a much smaller boat. I prefer a larger boat with more room for camera and video gear. Otherwise, Id rate both companies equally.
Little Cayman:
They all go to the same sites and use similar (Newton or comparable) boats. Its the cost and quality of the rooms and food that make the difference.
Pirates Point wins hands down if price is not a factor. They are at least 30% higher than the others. Their rooms and food is much higher quality than any of the others. No comparison.
Southern Cross is my preference because their rooms and food are better than the others except Pirates Point and their prices are much lower. You can always go over to a different resort and have a meal there if you want. Just dont purchase the meal package and go ala carte, that way you can bring snacks or eat at other resorts if you want.
Little Cayman Beach Resort and McCoys are the worst, for different reasons. McCoys is really run down and not all that cheap either. Little Cayman Beach Resort is way too expensive considering the small somewhat rundown rooms and terrible food.
Ill try to dig out some of my old dive photos and see if I can post them to show the differences and show exactly what I am saying, particularly about the north vs. east diving comparisons on Grand Cayman. But like I said, I dont live there, dont own anything there, and dont have any reason to pick one place over the other except doing a lot of dives and many of them in the Caymans.
I've also found some great shore dives on both islands over the years and I'll dig up my log books and post some of that too if anyone is interested. One of them is on the north side of Grand Cayman called Babylon, about 100 yards from shore but one of the best dives on the whole island, even better than most boat dives. I have found a few 'secret' spots on Little Cayman too over the years.