A smart approach would be to work your way to the top by generating affordable leads in a short amount of time with a small amount of budget by bidding on lower position, higher quality keywords. Then start to scale.
If you are launching a new product, there are a few ideas to get it out there.
Avoid sending hot leads to competitors and gain extra data for optimization opportunities.
DSA Campaigns are used as learning experiments - You may choose to build dynamic search ad campaigns because they help you learn what ad copy & keywords to use in the other campaigns, in case you missed any important and effective words.