We have grown the Mammoth and the Oregon sugar pods we only grow pole peas to utilize the small spaces we plant in..Both grow very well here in Montana zone4/5..It does depend on what your looking for in a pea.
We prefer the Mammoth since we do stir fry it also seems to hold a bit longer on the vines if ,, ummm someone is a bit slow getting out to pick,,,
The Oregon sugar pods fill up more since they are sugar pod peas and then they age quickly in our opinion..The pods seem to get a bit more chewy then Mammoth..
This year we are planting only mammoth our saved seed first planting is up and growing well,, The second planting from purchased seeds has not popped yet, but with all the rain it should be making an appearance soon...
Perhaps someone who lives a bit closer in your climate will pipe in as well..