like i see it can print in 20microns
That is completely irrelevant - You will NEVER print at that resolution. Even a small item would take all day.

The highest resolution you are likely to print at regularly would be 100 microns 0.1 mm

Also things to look at are build volume and does it have a heated bed.
If itnhas aheated bed then it will potentially print all the filaments that are out there.