Well done on your acquisition CA!
A good bit of kit on a par with Stihl for quality and robustness.
Advice? Ensure you keep the head well lubricated (Stihl Multi-Purpose Gear Grease).
Throw away the spool and get yourself one that takes pre-cut lengths of strimmer cord. These are inserted into the the spool and locked in place by spring loaded blades. No more tangled strimmer line, plus it's far more economical buying the line on the roll!
Buy quality branded nylon strimmer line such as Stihl, not the cheapo plastic variety. I've got a bladed brushcutter which rarely sees the light of day. My Echo deals with 90% of the work, and that includes docks, thistles, and a fair amount of woody growths.
Word of warning though, don't use near plastic electric fencing posts! It'll reduce them faster than a plastics recycling plant!