Yesterday I took a 16mm flat bit and made a hole in some plywood. The result wasn't as neat as I would like. There was a lot of splintering and big chunks kept jamming the spinning bit.
The bit is probably too blunt but instead of sharpening it is it necessary for me to get some forstner bits? Are flat bits really for situations when neatness is not important?
You should only use flat bits where the quality of the finished hole is not an issue. You can neaten up the result by going to a huge amount of effort to clamp sacrificial pieces front and back.
Keep the flat bits for the crap stuff, where you might hit a nail and buy some good quality Forstners. If you are a Festool junkie then the Zobos cannot be beaten but there are a lot of very high quality competitors out there. Once you buy them, look after them and do not make the two fundamental silly mistakes that I made with my Zobos...
I had been experimenting with precision hole production methods and dropped a Zobo on the concrete floor which it hit tip first. I bought a new one and less than a week later hit the remains of a broken screw in what I had thought was a virgin piece of wood. I had one of the Zobos sharpened professionally but it is not quite the same.