InfoPath Dev

I would like a theoretical answer to this....

I am using IP 2007.  I have a form that once submitted to SharePoint, will be emailed sequentially to up to 3 approvers.  The approvers are saved in a SharePoint list. Once a dropdown field in the form is selected, a data connection to list autofills in 3 textbox fields on the form.

After the 1st approver is notified, they open the form and click an approve or reject button.  IP Rules identify the user and if it matches the 1st approver and the form is "awaiting 1st approver"  it allows the user to click either button.  If they click approve button, then the next email is sent to the 2nd approver and so on.  I only send an email when a button is clicked. 

So my question is, is it better or more efficient to send the emails with a SharePoint Designer workflow or better to write InfoPatch (C#) code to send the emails?  I haven't written a designer workflow yet and I assume one difference is (in my scenario) that the designer will identify when to send the email based on status change of the form (versus a button click), and in infopath code I can send the email on button click event handler?

In the button click event I could either retreive the email address from the forms' textbox or from the SharePoint list directly (which is better?--another question), then pass the value to the C# email adapter code....

I've done it both ways, but lately I've setteled on handling the approval workflow inside of InfoPath. I find I can control it better than a SP workflow.  One of the ways to accomplish this is to use muitlple views for the approval. Additionally, I use a view to construct/customize the email message. When the user approves, I have rules that change the view to the email message view, update the field(s) with custom information, fire the email submission, then switch the view. It happens fast enough that the user never sees the view change.  Here is a very good blog post by Laura Rodgers on the subject:

http://sharepoint911.com/blogs/laura/Lists/Posts/Post.aspx?ID=113

Thanks for the link to tips from Laura.  I watched the video and got some great ideas.  I managed to build a simple approval workflow with SharePoint Designer that is working quite well for now but in future endeavers I will try creating the workflow inside the form itself.  One thing I hadn't thought of was creating a read-only view for the approvers to prevent changes.  I will incorporate this into my form for sure!