I agree CyberJack, there is still a place for edgers like the 38. I have ended up with 2 Victa TaC's and 2 Alroh imps, and they go well around the straight traditional edges (in this case a garden designed in 1987).
I also have a Ryobi expand-it stick edger which is good
The lawn shape was made by my grandmother (now 90) and reflects the traditional thinking - dead straight edges.
They had a kidney shaped garden bed in the first house they built in the early 50's, but the subsequent houses all had straight edges. They entered in all the local garden shows, so everything had to be perfect.
From what I can piece together, Pop at one point bought a SB edger to complement a 45 - used it once then went back to the traditional wheel edger and half moon edger.
Personally, the problem I have is the back lawn is surrounded by slabs which are no longer a perfect line - meaning I have to use a line trimmer.
I use a straight shaft homelite with the gearbox turned 90 degrees. And if I take one chunk out of the lawn, I won't hear the end of it for weeks

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Pair that with the uproar caused by the non-resistor plug in a victa causing interference to the TV whilst Bold and Beautiful was on, and how I left the fuel tap on whilst finding another plug and killed a good patch of lawn through the needle leaking - those caused real issues.