I have the 650 version and the auto feed has been great, also had issues with cheaper ones bought in the past this strimmer has been fantastic , the only drawback in 2 or 3 years has been the weight , it’s quite heavy
Got my WORX one when Homebase were closing down so it was cheap but too late now I'm afraid. There's a fiver off this one but only one small battery: https://www.ebay.co.uk/itm/WORX-WG157E-18V-20V-MAX-25cm-Cordless-Grass-Trimmer/183302301280?epid=4033842567&hash=item2aadab2660:g:1cYAAOSwe-hemEXN
Sthil petrol (y)
Until it won't start! Mine dribbled burnt 2T oil all over me too.