I'm big on gin n tonics but am curious about gin martinis. Anybody have tips or a certain vermouth to try?
There is no such thing as a gin martini. A martini is gin and vermouth. Period. Any vodka-containing mixtures should be labeled as vodka martinis. Anyone who disagrees is wrong.
Also, it's tough to compare Bombay and Tanq because they're such different creatures. Bombay is pretty dry, without a lot of coloration to the basic juniper-ish taste, whereas Tanq has all kinds of floral flavors mixed in that highlight and enhance. I wouldn't say one's better than the other, but they do different things, and it's kind of mood dependent which one is the better choice. I personally prefer Tanq in martinis, but that's because I normally don't use a lot of vermouth and want some more flavor notes to consider.