According to my knowledge In "Grouped Product" user has the choice but in "Bundle Product" user doesn't have the choice.
To practically check "Grouped & Bundle" Product feature, I created a Test product of both type.
Please visit here to see screenshots:-
1- Grouped Product:-
But as you can see the screenshot user is not restricted to choose all product. he/she still has a choice to choose the product for "Bundle Product".so how can we say that "Bundle Product" doesn't have any choice?
Please let me know how they are different?
Waiting for your reply!!!