Nearly all of my beans are pole. Common beans, limas, runner beans, yardlong beans - there are numerous pole varieties to choose from. SSE lists more than twice as many pole beans as bush beans, so there is greater variation available in pole types. In the case of yardlongs, runner beans and limas, there are relatively few bush alternatives. In warmer climates, you can add hyacinth beans & winged beans to the list of pole varieties.
My garden philosophy is to garden vertically as much as possible; so I choose varieties of all vegetables that will climb, when I can find them. Pole bean varieties keep the pods up off the ground, reducing losses due to rot, slugs, & rodents. Overall pod quality is better, regardless of conditions. The yield per plant is higher, and sustained over a longer period. Since I save seed for beans in a frequently wet climate, I appreciate that the elevated pods dry out quickly after a rainstorm, minimizing losses. And... you won't find a bush bean to match the spectacular 10-11" pods of Goldmarie or Fortex, the 24"+ pods of yardlong beans, or the huge shelly beans of Bird Egg #3 or Gigandes. Yeah, you can't eat bragging rights - but it does contribute to the fun.
Growing beans vertically has other advantages. Tall trellises act as windbreaks, so they can be used to create micro-climates, which then shelter tender vegetables from cool winds. In my climate, okra, eggplant, and moringa benefit from this arrangement. The trellises can also act as barriers to pollinators when seed saving, to reduce crossing... which can be very effective in combination with trellises of other vegetables (such as squash, gourds, and cucumbers). Pole beans can be inter-cropped with other tall crops for support, such as in a 3-sisters garden.
And since my climate is temperamental early in the season, I can start pole beans as transplants, and get a substantial yield from only 10-16 plants. That is a make-or-break difference some years, especially when saving seed, or stretching my growing season for a long DTM lima.
Bush beans do have a few advantages, other than ease of planting. While there are a lot of pole dry beans, most of the popular varieties are bush. In general, bush varieties have shorter DTM's, which is an advantage in short-season climates - especially for dry beans. Bush beans tend to bear all at once & be done, so where the season is long enough, that space can be utilized for other crops in rotation, such as a Fall crop of cool-season vegetables. In very windy climates, pole beans may not be feasible, while bush beans will tolerate some wind. In arid climates, bush beans closely spaced will help to conserve water, reducing the need for irrigation.
About yield... I did a comparison one year, between the dry bean yield of several different bush & pole varieties. For single rows, the higher yield per plant of pole beans will eclipse an equal row of bush beans. With blocks or multiple rows, this advantage is lost. Given that shading limits the spacing of adjacent rows of pole beans & you can space bush beans closely, the yield per square foot actually ended up pretty close to even. The advantage? With pole beans, the paths are inherent due to spacing, making harvest easier. Harvesting in blocks of bush beans is more difficult.
Yes, building & tearing down the trellises each year is difficult (especially with 400-500' of trellis) but that is offset by an easier time finding pods & reduced bending during harvest. Perhaps the day will come when I am no longer physically able to erect the trellises, and have to fall back on bush alternatives (which I already have), but for me, the advantages of pole beans are too numerous to overlook until that day arrives... which I hope will not be soon.
