Welcome!
An interesting career!
Lots of help available on here if you feel the need.
Have no experience of the Optimum, but search back in the Forum for Brian John's experience of his. As a newbie, he may have made some of his problems, but his experience, down under, was unlike any of mine with new machines.
In UK we are fortunate to have several importers, and folk seem to have fewer problems with the machines that they sell.
generally, having four different far eastern machines, have not been too disappointed. Yes there have ben a few problems, but none that cannot be overcome with care and adjustment.
One model of machine did have to be returned twice, before choosing a different version that worked well for years, before having a fairly easily overcome problem.
We are in a cost sensitive, and therefore more variable quality, area of the market.
Maybe, you should pursue seeking experiences of any machine, and the after sales back up provided by the importer, before purchasing.
Good luck
Howard