I’ve always found Flymo’s very hard work and pretty crap to keep going in a straight line.
I currently use a Bosch electric thing is it better than others, havent got a clue, but its not as hard work as the Flymo.
If you want stripes you need to get a traditional style one with a big heavy roller on the back. If the garden is perfectly flat, sqaure or rectangular they are easy enough to use, if not a real pain.
People I know who have power mowers are always at some point struggling to get them going…
Electric is good because it makes a very loud bang when you cut through the cable. (well at least it did when my brother cut through his)