The Gun boat is quite weak though, and when you're being assaulted from all angles, I prefer to use the Fork boat, the one with the flame paint. I don't really attack them, I just try to outrun them, and if it gets badly damaged, I repair it. It really doesn't cost that much if you have hundreds of millions of dollars like I have. For my on land drug runs I use the Albatross. It's far and away the best vehicle to use, because the handling is superb and you can pretty much outrun any car after you. I hope that's the car I mean, I think it's the one with the doors that open upwards, like the Back To The Future car. I also get huge amounts of money for each drug run, I'll be disappointed if I don't get upwards of $20 Million. Occasionally I use the Armoured Car, which looks like a SWAT police van, because it's next to impossible to get destroyed.
The last time I played this was at least 6 months ago, so all this is off the top of my head. Hopefully most of it is correct.