In the Budget oriented structure, a separate campaign is created for each ad group. The advantage of this structure is that you can define the budget for each match type separately at campaign level. This gives you full control over which match type gets how much budget. In addition, individual settings can be made for each match type with regard to the bidding strategy and the bid by placement in order to achieve the individual marketing objectives. For example, product ad groups can be forced to be displayed on product detail pages. For this purpose you can set the keyword bid to a relatively low value and choose a large multiplier for bid by placement.
The Overview oriented structure creates a maximum of two campaigns, one for the auto ad group and one for all manual ad groups (Broad, Phrase, Exact and Product). The advantage of this structure is that you need a maximum of two campaigns and all manual ad groups are organized in one campaign. If you do not pursue an individual strategy for individual match types, you can easily define and change the setting of the bidding strategy and the bid by placement using the manual campaign.