[help buying new string trimmer]

I got an 18v Ryobi and it works good! mostly my problem is pull cord or locking up for the gas models

[help buying new string trimmer]

don't have any other Ryobi tools.... have the 6 piece dewalt kit tho.....

[help buying new string trimmer]

I only live on 1/2 acre, but have less than that to string trim.... 

[help buying new string trimmer]

was looking at getting a cordless string trimmer as I now have like 4 dead gas powered string trimmers

 

what would be your recommendation on one? I was looking at the Ryobi 18v and 40v and I like them, but what do you recommend? and no, I'm not looking to buy another gas powered one!