What do you want to be able to do with it? Are you happy with sticking to standard resolutions or will you want to do custom sized canvases, blends etc? If it’s just switching standard sources I don’t think you can go far wrong with an Atem TVs 4K. It’s all SDI but you’d have plenty left to build a nice accessory rack with a monitor and some convertors. The TVS 4K has the nice trick of input scalers, so you can mix and match on that side of things. Contrary to Mac’s experiences above we have had generally good times with the analog way stuff we own, we run an Ascender which has done us proud over the last four years. Lots of very different events under its belt.