The Welkin Suite offers an integrated development environment with 105 features (and growing). The vendor aims to help you automate the chores of development, and therefore enhance your coding velocity and increase the quality of your deliverable code.
I have tried using the Developer Console, Microsoft's Visual Studio Code with the Salesforce plugins and also Mavens Mate along with Sublime. The latter is deprecated. The rest are either options that are not as fully featured as The Welkin Suite or their setup time is much …
The Welkin Suite is a great IDE compared to the alternatives out there. If you need to code in Salesforce and you want a mostly seamless environment, then The Welkin Suite is the best option available, in my opinion. I have also been using it for Apex Tests and find that the tools are really good for measuring code coverage and highlighting those areas that are uncovered.
It would be nice if IDE feature releases were timed to coincide with Salesforce releases (i.e. make Lightning Web Components available on the day they become available in Salesforce instances).
The IDE can be a bit buggy especially when you have several windows of the IDE open to different Salesforce instances at the same time on one machine.
Sometimes, when you click to retrieve your data too soon, before the program has a chance to ask you to connect to the instance, it can cause the IDE to freeze.
In general, when you need support there is someone there to give you an answer. I think there could be an improvement in this area, but it's hard to provide a substantial amount of support for a product that is charging roughly $15 a month. Do I feel I get more than $15 worth of support value when I need to request it? Yes.