I do have some .155" string; used in my wheel trimmer. I don't think the little 128LD has the horses to run more than a few minutes before exploding :laughing: Of course, the reason I use the 128LD size is for the 7# light weight. I "think" I've found a good solution though and that is I've found a closer fitting head guard similar to the one Tanaka uses. I'll be giving that a try in a few days, after the rain stops.
I do have and use the metal blade; 32T x 8" carbide. That works pretty well for small brush and to knock down weeds. It's a rough cut though, so coming back over the same area after a couple of days for the wire weed to dry out is necessary.
The metal blade, although a serious tool, is also seriously dangerous. I've seen the results caused by the operator hitting a short stump and/or rock. It slung the trimmer back at him almost cutting his head off! He lived, but carries a 10" scar across his neck as a reminder. So, when one does use the metal blade, extreme caution should be used, and the risk is assumed.