It's easy to use it is fully compatible with other AWS services like Lambda, API Gateway etc so there are no limitations when you build your applications in pulumi! You have full control over all aspects of code deployment (e.g., versioning).
There isn't much I dislike about this tool but maybe some features could be added such as lambda integration which would make life easier if we want our apps deployed via pulumi only. We used pulmuicloud mainly because its compatibility with existing aws solutions eases up development process by allowing us not worry too much how will things work together later down the road. Currently being developed new app that uses both VPC + CloudFront CDN setup along side another service called S3 storage backend - pulmui provides nice abstraction layer here also since everything can run within same environment without having separate.