Yes Weight watchers core and SW extra easy are very similar. But like with all things they both have pros and cons;
On SW you can only have a measured amount of cereals like porridge, bran flakes etc which you don't have to measure on WW. But on the positive side with SW you have a wider selection to choose from such as muesli, honey nut bran flakes, cereal bars like alpen light etc. Same goes for milk, you can have skimmed milk freely on WW but have to measure it on SW but you can also have semi skimmed or even whole milk in measured amounts. Oh and we can have cheeeeeeeese and bread without having to syn or point!!
On WW core you can only snack on fruit and veggies (without pointing) but on SW you can snack on any free food!
At mealtimes with WW you can have certain foods freely that have to be synned or counted as an HE on SW, such as tinned soups, gravy granules etc.
On WW core you can't have any convenience foods but on SW you're allowed some like pasta & sauce, savoury rice, couscous etc.
The best thing about SW for me is that we are encouraged to eat generously. As a result I've come to find my own comfort zone with identifying my fullness. With WW core where the emphasis was on not eating beyond satisfaction, I'd spend every mouthful of food worrying about whether or not I was full so I was always a bit apprehensive at mealtimes and ended up eating less and was hungry a lot of the time.