Tony, I suspect they could be a lot better, if the mechanics were super robust and precision pieces of work. For the price we can pay, they are not - they are pretty rough bits of work at this low end of the market, certainly not "precision german engineering". Regardless of the flash paint jobs and fancy stickers! So screws wobble, springs are pretty weak, tubes and bases can flex etc.
We'd rather pay the money for good optical surfaces and put up with the face that we have to play with the mechanics to get the best out of them. Collimating a basic newtonian reflector to acceptable, even good performance, is straightforward, even without the mods we make.
But even the best scientific equipment (I worked on million dollar mass spectrometers for years) needs calibration and adjustment.
Eric
