1.As opposed to widely held belief that ...,I believe that ...

2.Contrary to generally(commonly) accepted ideas(views) ,I argue that...

3.Although many people believe that ..., I doubt whether the argument can bear much (further) analysis (close examnation).

4.The advantages of B outweight any benefit we gained from A.

5.Although it is commonly(widely/generally) accepted (held/agreed) that ...,It is unlikely to be true that ...

6.(Indeed)There is an element (some elements) of truth in this argument(statement), but it ignores a deeper and more basic (important/essential)fact that ...

7. It is ture that(Ture,To be sure,Admittedly,) ..., but it is unlikely(it won‘t be the case/it does not mean ) that ...

8.The main (obvious/great) problem (flaw/drawback) with (in ) this argument(view) is that ....