You can't really go by tip suggestions, it's all about your ears. I have tried the star tips, and none of them fit, the long ones are too long, then the others just won't seal properly. From the stock tips the black foams aren't quite the right size for me either. Yellow foams are okey size wise, but the surface is too grainy for them to be comfortable. What i have found best universal tips are the included silicon tips in medium. They stick to my ears like suction cups, and are pretty super comfortable. Later i bough the comply comfort(Ts-100) they are exactly the same size as the shure silicons so they fit pretty good for me, but i still prefer the silicon's for their smoother surface. Later on i have got custom molded tips, witch isolate and fit great, it's just that it takes little effort to put them on and take em off, so when out and about there are benefits for universal tips, at least you can get em off easily when someone talks to you etc.
I would say that don't buy any other tips unless the stock ones just won't fit. If you need something in between shure medium/big the star tips might be okey. If the shure silicon tips are great, but you want to go for foam, comply ts-100 are great then.