kernits

The unifi stuff is great but single power supply so really not suitable for a "core" switch.

We used to get get all our unify kit from MSDist but 4Gon have been loads cheaper recently especially on CCTV, they are a pain to get an account with but we go there in the end. We have 22 switches, fifty odd APs and 60 odd cameras, it all just works and allows us to have the sort of performance we could not afford with other manufactures. The total cost is not unlike some will try charging per year for ongoing licensing alone...

We have local storage rather than a SAN with one server having a mix of SSD storage and mechanical. All VMS that run SQL are on the SSD array. Our budget is tiny for a secondary so a SAN would never be possible. It is the best I can do at present.

Moving the SIMS server to SSD storage made a big difference for us. The queries which took an age to run and locked the DB now take a fraction of the time to run which then mostly stopped the complaints.... if your not that familiar with SIMS definitely worth getting the support provider to check the patches, and that the housekeeping stuff is being run. We are on SQL 2014 and have had no issues since the CTF patch dramas.

Have run VM only DCs for best part of a decade never had a problem so far. Other than making sure time source is setup correctly and that the PDC is not getting its time from the hyper-visor. We also used fixed size disks for everything and do not use dynamic ram. Agree with FishCustard try and keep the hosts the same if possible. If you are going for a shared nothing approach then you need to think about how you will maintain the host os. If you plan on no down time then one server need to be capable of hosting all VMS while the other is being updated / patched.