Arcadia has kept us in broccoli, LOTS of broccoli, all summer long. The plants grow grow tall and bushy with many growing points per plant. After the initial big head the side sprouts grow smaller heads all summer and into the fall and early winter. (I'm at 1400' in western WA so I grow my Arcadia in a hoop house.)
My broccoli looks great at the moment. Heads are forming and just about ready!! Pinetree is a great place to buy seeds, especially small packets! I had great germination also.
I've always liked the fact that I can buy an appropriate number of seeds for a home gardener- for instance, 15 or 20 tomato (or broccoli) seeds are more than enough even if I spill a few or have some dampen off. This keeps me coming back year after year!
I live in central FL so my growing season is Oct. to May. I picked the first head on Christmas day and was still picking in April. The first heads were huge 8 to 10 inches across. The plants then produced multiple 5 to 7 inch heads, then buckets full of 1 to 3 inch side shoots. Great flavor and freezes great too.