I haven't checked out the high-level synthesis part, but I've been using Vivado for a project recently and it's absolutely horrible. To name some of the issues

I haven't checked out the high-level synthesis part, but I've been using Vivado for a project recently and it's absolutely horrible. To name some of the issues I've had; - Memory leaks (grows from about 1GB to 11GB and starts swapping in a couple of minutes when editing existing IP) - Single-threaded synthesis is slow (though isn't limited to Vivado specifically) - Failing after 20 minutes of synthesis because of errors that would be easy to check at the start - Placing debug cores can result in needing to synthesise, find something went wrong, delete debug core, re-synthesise, re-add debug nets, synthesise again... - Aggressive caching results in it trying to find nets which were changed and no longer exist, despite re-creating the IP in question from scratch - Vivado creates a ridiculous amount of temporary files and is a royal pain to use with version control (there is an entire document which details the methods to use if you want to create a project to be stored under version control) I've been playing around with IceStorm for the iCE40 device and it's an absolute joy to use: fast, stable and simple. I appreciate that there are a lot of complex tools and reports which Vivado provides, but I would much rather use an open source tool like IceStorm for synthesis alongside the advanced tools from Vivado.