We've been building executables and vipm packages on Azure for quite a while now and most builds work. Our driver package (6500 files) takes about 45 minutes on a pretty low spec PC. Applications usually build within 10 minutes.
All our builds are LabVIEW 2018 64bit though, no multi-version doom. But there's no reason why you couldn't build multiple versions.
With Azure build pipelines you have the choice of either self-hosting your build server or using an Azure VM which you have to install the complete toolchain on. Azure VMs can spin up/down on demand which is supposed to save you money because you only pay for the time they're up. We're not doing that.
Another cool thing is unit testing. The caraya test framework integrates nicely and posts your test results stright to the pipeline. More here: https://forums.vipm.io/topic/3293-unit-testing-with-azure/
Happy to share more thoughts - probably in a different thread or PM