There were not as many options to get from Brunei onward to Sarawak as there were to get into Brunei from Sabah. We could have taken 3 buses, but it would have taken a couple hours longer and we wouldn’t have saved much money. It’s much easier to go straight through, than to have to keep catching connecting buses. So we just hired a private car (directly through our hotel) since flying was not even available (flights were available to Kuching, Sarawak, but not to Miri). The drive was only about 2 hours from Bandar Seri Begawan to Miri, even faster than we’d expected since we were traveling on a weekday! We paid 90 Brunei dollars (US $60), which was a lot, but it was a smooth and easy ride. We didn’t even have to get out of the SUV for immigration. Our driver just handed our passports to the inspectors from his car window.
We checked into the Palace Inn in Miri and headed out to dinner in the evening, but almost all of the restaurants were closed! So if you want to eat in Miri, go early, or there may only be one option. The Palace Inn was a bit run down and shabby, but it had free WiFi in the rooms, was super cheap (US $15/nite), and the lady at the front desk was nice. If you want a nicer place (maybe USD $10 more per night), across the street is the Somerset, which also has free wi-fi but only in the lobby. We also found a cheap laundry mat around the corner.