Hey there! I use both email services. I use my Gmail account when signing up for most sites as they tend to send a lot of emails I'm not very interested in. I use outlook as my personnal email, and I tend to check it more often and respond faster. When it comes to the performance itself, they both have their advantages and their pitfalls. Google has a very easy-to-use interface and is very aesthetically appealing. If I'm talking about Outlook, I just like the sheer amount of options for customization. My dad runs his own mail server, so I'm able to have a custom domain, more advanced rules for things like mail sorting and detecting junk-mail better. So when it comes down to it, personal preference is really the deciding factor; if you just want something easy that works well, Google is a great option. If your a person that likes everything a very specific way or just the freedom of modifying whatever you wish Outlook is probably better suited for you!