Id always opt for Nandos as they have loads of low syn options. But its not something I can really help you with as I don't really know what you like? Or where you would of went pre sw. If you have the book handy check the back in the syns section it gives great options for ayns in different restaurants etc. I always keep my book in my handbag for when I'm out and about so I can opt for most sw friendly options. Like a tomato based sauce vs a creamy one. Or like choosing steak with boiled baby potato's and veg or baked potato with beans etc etc
I used to love harvester but not so keen on their current menu... However in saying that, they have loads of chicken options. Their sauces are served on the side, you can have a jacket instead of fries - and it all includes unlimited trips to the salad bar!!!!
I also like wetherspoons as they have some really low syn options too so ideal for SW