If you text with the phone upright it’s a pain because the letters are close together, even worse if you don’t really have fingernails to press the keys. I find that holding the phone sideways is better and I think it’s pretty accurate for being a touchscreen. Some words I mess up but I have heard it’s an issue on other touchscreen phones too and not just the Omnia.
As fas as randomly shutting down, I haven’t heard of anything like that and haven’t had that issue with mine yet.