Hi Catito,
I will try my best to answer your question with a little bias as I can. We pride ourselves on top notch service and the best experience. So does Ocean Frontiers. Both are excellent choices but very different in a vacation experience.
Ocean Frontiers is located on the east end of the island which is a very different feel. You actually feel like you are on a Caribbean Island. There are fewer attractions and and restaurants. Most of our staff will take 'staycations' or day diving trips to the east end and dive with our Ocean Frontiers friends. Their boats are large, their crew is great, and the experience is worthwhile. OF is on the Compass Point resort, and as such is a more traditional resort atmosphere. Mostly guests do not get rental cars, and use the resort amenities. If you chose to go off-site, there's really only 3-4 restaurants to chose from. At the time of this writing many are closed due to the COVID border closure, although some will reopen. OF and Compass Point are more of a relax, dive, drink sort of atmosphere, and there are many that prefer this sort of relaxing vacation. There is a beach on the east side, but it's within the barrier reef, so it's not nearly as nice.
Divetech on the other hand is located on the West side, just north of the hustle and bustle of Seven Mile Beach. The accommodations facilities we offer, are the condos we have on premises All are privately owned and some are in short-term rental. Guests here tend to rent a car, and will dine out at one of the hundreds of restaurants that dot Seven Mile and Georgetown. Our boats are also large (a tiny bit smaller than the OF newtons) and our crews are just as awesome. Divetech is more of a "let's see the culinary capitol of the Caribbean" sort of atmosphere. There are many who prefer the diverse scene and amenities offered on the West side. West Bay has Seven Mile Beach, which is your traditional white-sand, turquoise water Caribbean beach.
What sort of trip you'd like obviously depends on you. Some of our customers will do both on the same trip. It's not uncommon for someone to stay with us for half the vacation and then stay with OF for the second half.
** Biased alert ** Divetech offers shore diving, scooter rentals, and technical/rebreather try-dives and support which OF does not have. OF has sharks, and plenty of them, which we generally don't get. Although some will say the diving on the east vs the west is vastly different, I find for the most part it's largely the same topography underwater.
Tony