We have a studio condo at Sand Dollar and have rented trucks for years. We also advise our rental guests on arranging rentals.
Be aware that trucks are NOT covered by your credit card's car rental insurance policy. When the island accepted AmEx credit cards, we signed up for the AmEx Premium Car Rental Protection program. For an annual fee of $19.99 or $24.99 (higher limits), AmEx would cover your truck rental for up to 42 days! Amex automatically charged this amount to your card when it saw a charge from a rental car company and covered you for up to 42 days per rental.
Most rental car companies and most businesses on Bonaire no longer accept AmEx. Their fees are too high.
I have never used them but many swear by Telerin for truck rental. I have used AB Carrental, Total Car, Avis and Budget. I tend to go with the cheapest and get the least expensive truck available. AB trucks often are in bad shape. But they run and they replace them if you have issues.
Here's a listing of many of the car rental companies on island.
I am surprised to hear that the OM1 is huge. I haven't seen one yet. But, I don't really want to purchase another huge system for UW. It's hard enough to schlep around the D80 Ikelite system, which stays in our condo in Bonaire most of the time. (I take it home for service every couple of years.)
With any compact system, the shutter lag is a huge concern for me. I know folks who use the EM5 underwater and they get very nice results and no complaints about lag. I am surprised to read that you experience lag. I thought Olympus had improved shutter lag so that it was non-existent.
Topside, I know what you mean about needing some weight in the camera body as a counter balance for a long lens. I tried a superzoom Canon point and shoot with a 40x lens for super telephoto. It was difficult to hold still, difficult to see through the LCD and tough to get long shots. It was a gift but I couldn't use it for tele shots and it wasn't much better for other uses. Bummer.
Both of these cameras are at the top of my buy list.
I am hoping the camera will replace my DSLRs for topside shooting. I love birding, especially shooting from our canoe on river trips. I take tons of pictures (landscapes and people) in all our travels in all kinds of lighting and all times of day. And, I take the DSLR in my dry bag on whitewater canoeing trips and take pictures of my river buddies surfing waves and running rapids.
One attractive thing about the micro four thirds system is the crop factor. I am hoping that I can finally afford to buy a lens that will give me crisp, sharp shots of birds in a 600mm or more equivalent focal length compared to what I get with my Nikons and a 70-300 Nikon zoom (soft, not a good lower light lens with my D300).
How will either camera perform for this kind of topside shooting?