Hiya
I did SW when I was pregnant and had great success keeping the weight down. I do love the plan but I've never been successful long term losing weight but WW has always been my weight loss route to success.
Both plans are great but it depends on your lifestyle and how you want to commit to losing weight.
If your prepared to cook your majority of meals from scratch, have good portion control and be prepared to stay within a limited amount of 'treats'. Then SW is the way and you will be rewarded with no weighing and hopefully weight loss.
If you want the freedom of having the option of convenience food, are prepared to weigh everything and count your points then WW is your way.
You do also have the option that you can follow WW Simply Filling which is very familiar to SW.
I have simplified the above to just the main commitments I believe you have to give to get the results. Obviously there is a lot more to both plans and to go into real depth would be one big post lol
I honestly believe that your main decision has to be down to how it fits with your lifestyle. If a diet doesn't suit you then you will struggle to be successful.
I hope this helps, if not just ignore ha ha ha