If you want to talk the differences in beans
@Zeedman is the one to ask.
I've been growing mostly heirlooms. Yes there is quite a difference in the taste of many of the varieties. Take Tobacco Worm for instance a favorite of many has a strong beany flavor that for me I had to acquire a taste.
Then I was introduced to full beans, these you let the beans fill the pods before picking e.g. Tennessee Cutshort, absolutely delicious. There are many more varieties you can eat this way, the pods stay tender even at this stage.
Annette
Annette, I think you've grown & tested more varieties than I have... all the more remarkable given your climate.
longer and skinnier bean pods.
in my experience harder to get seeds from the fillet types here, but i've only grown a few so far.
Agreed. The filet types have long, straight, round, very slender pods when young. They are very slow to develop seed - which is one of their best traits, since they remain tender even large & have a longer harvest window than most snap beans. Two of the pole filet beans (Emerite & Fortex) are some of my favorites, because they are stringless & have very high quality when frozen. There are several bush filet varieties also, which I have never grown. Vermont Bean carries a wide selection of filet beans (bush and pole) including a bush
wax fillet bean, Soleil, which I intend to try.
The pole Emerite, IMO, is one of the best beans for canning. I grew it this year for freezing, for making canned dilly beans (which turned out really well) and to renew my seed. It has outstanding cool-soil germination, and produces a heavy crop here even planted as late as July 4th. Yes, they took a very long time to go from snap to seed. I was still picking some dry & near-dry pods just before frost... but the seed yield is high. I ended up with over 3# of dry seed, enough to grow & share for 7-8 years.
As
@aftermidnight mentioned, the classification of snap beans can be a little complicated. You could classify by pod shape (round, semi-flattened, Romano); pod color (green, purple, wax); stringless or stringed, etc. Appalachian beans include additional categories; crease back, greasy, half-runner, and the "full" beans mentioned above... it's a pity that Bill Best (or Dar Jones, who posts on other garden forums) isn't here to comment on those. It's enough to make your head spin.
Personally, I tend to categorize snap beans as round pod (which includes the filet types), Kentucky Wonder types (with flattened or squarish pods), and flat Romano types. The round-podded varieties that I've grown tend to be sweeter, often stringless, and are some of the firmest for canning. The KY Wonder types are stronger flavored, and tend to have a shorter harvest window; but they can also be incredibly productive. The Romano types are some of the earliest pole varieties (such as Early Riser and Goldmarie), and many have a unique sweet pea/bean flavor. Two Romano-type pole beans I've grown (Champagne and the purple-podded Czechoslovakian) were notably more productive in heat than other beans grown the same year. Some of the flat-podded beans (such as Bosnian Pole) are also dual-purpose, being good as either snaps or shellies.
Then too, there are runner bean snaps. Those are best suited to cool climates, where common beans struggle.
I try to grow at least one variety of each of those three types each year, and at least one wax type. Like Russ and Annette, most of the varieties I grow are heirlooms. The wide variation in flavor, texture, and usage is what makes beans so much fun to grow, especially given the lack of diversity (except for dry beans) sold commercially. I'd be happy to send a sampler of varieties for trial.
Oh fudge... started looking at Vermont Bean's online catalog because of this thread, now I'll have to order a few.
. That's not the impression of the variety that I want to give 
. It's a very nice, tender green bean.
