I like the fact that Smartsheet provides alerts, approvals & actions workflows built into the application. This is handy and can be established in templates to provide some consistency. I'm also a fan of the Charts implementation. If only the Dashboards were better they'd really shine.
The project management functionality is honestly woeful. Before it can be considered as a true Project & Portfolio Management tool, there are some fundamental gaps that need to be addressed. At this stage, if you are running more than a few projects, have professional PMs in your employ or have a global team, then look elsewhere.
Locales are practically useless, as everything is treated as UTC. If any changes are made (e.g. new sheet, row, or updated cell), depending on where you are it can show up as the previous (or even next day) because it assumes you are at (UTC 0). I'm in UTC +10 so if I make changes at 8 AM, it's recorded as yesterday. Not good enough for project management or any reporting I've ever been involved in.
Smartsheet also ignores anything other than US date formats in some situations. Even if I set up my profile (and locale), it sometimes still assumes that 9/5/18 means 5th September, instead of 9th May. You can see how that would be a problem in reports :-(
Throw in the inability to set project baselines, associate more than one resource to a task, create programs of work without having to reconfigure the very expensive Control Center add-on and the need to occasionally manually refresh dashboard data and it's certainly not a product I'd recommend to anyone looking for a serious project management tool.
I'd definitely review the Smartsheet Community website before going ahead. Read what others are saying, what is missing, the direction Smartsheet are headed in and weigh this up against what you're looking to get out of a tool like this.
Smartsheet is embedded in our company. There are many people using Smartsheet to record and disseminate a lot of data, so it's difficult to quantify or qualify realised value. But I really do not see anything that could not be accomplished with Office 365, Power BI and SharePoint (which we already have). Throw in Project Server (about the same cost as Smartsheet Control Center) and you have a much better solution.