I haven't owned a strapless or convertible bra in years. I keep seeing dresses and tanks that don't work with a regular bra. I think I'd like to get a convertible bra. I'm slim, but a little busty (34D or DD). What's a comfortable, supportive bra that doesn't cost too much and can be worn either racerback (crossed) or strapless? Since I don't think I'll wear it too often, I'd rather not spend to much money on it.