[thibaut_barrere]

I only tested SendGrid and Mandrill for transactional email.

I switched off SendGrid after seeing quite a bit of gmail owners got their email sent into spam (but I believe they fixed the issue).

I use DKIM/SPF with Mandrill and nobody mentioned a spam issue since then.

On SES: I cannot find back the precise article I was thinking about right now (a benchmark if I remember well), these are just my memories.

[ra]

I use SES with DKIM and SPF. It's fast, cheap and I've never had a single email go to spam.