Bring some of the stuff you will be cutting when checking them out. Ask them to cut a square inside a circle or some similar simple shape that you can easily evaluate afterwards. Fro the look of it I assume it will be very compliant in Y. Try to make a +-X cut, then go a couple of um out from the cut and back to where the cut was made. Then push on the top of the gantry. It will not surprise if you can cut several 10ths of mm just by pushing with one finger. Decide if you can live with that. It may work OK with small cutters in thin material. But if you try to put on more cut it will not be a nice surface and not where it should be. But then if you cut signs never observed up close that may not matter to you. Also machining times may be high, but being a CNC there is no crank that ties you to the machine.
