The ticketing side of HubSpot Service Hub is very flexible conveniently and seamlessly integrated with the HubSpot CRM. The line is blurred between ticket and conversation, which makes interactions with leads and customers more human (HubSpot's whole mission, essentially). There are good integrations with Calendly (new!), Appcues, Gmail, etc. plus the native features such as tracking knowledge base views, opens and clicks on emails, logging calls, etc. that make HubSpot a central record of all customer interaction and give us visibility on the whole journey. Associating a ticket with a CRM record (contact, company, deal) is easy and extremely flexible (unlike a help desk tool I've used before): in HubSpot there doesn't have to be an exact 1:1 relationship between all those things. We can just associate whatever message with whatever record it is actually associated with (helpful for cases like consultants who use our software themselves but also help out with other users' accounts). Plus, a couple other details: 1. being able to respond to live chat in Slack is great; ultimately, you need to view the customer/lead details in HubSpot anyway, but it's good to be able to send a quick, "Hi there, let me look into that for you!" even when I'm not on the chat page in HubSpot yet; 2. the "board" view vs. the "table" view for tickets is great to visualize the pipeline. Overall, I am pleased so far, and HubSpot shows a desire to improve this tool further.
The radical flexibility and pulling all information about the customer together can get overwhelming and clutter up the screen. Luckily, you can filter out whatever you don't want to see very easily, but it's hard to know what to filter out if you're not looking at all of it to begin with. The knowledge base is not nearly as flexible as the other parts of the tool, e.g. you can't have multiple knowledge bases, and there is very little ability to customize the look/feel (although they are improving this part). Some other things that are strangely inflexible: the support/ticket form (we opted to use a marketing form instead and build a workflow to trigger a ticket, at our HubSpot account manager's recommendation!); and teams (agents can only be on one team and can only view tickets for their own team).