I seem to recall reading that the sub-55 models were made by someone other than Stihl. Many Stihl dealers don't even stock these models. If I were you I would consider the FS55 to be the best starting point in the Stihl lineup as I have not heard any dependability-related complaints about that model. With the FS45/46 series there seem to be more ignition problems than the FS55+ models, a higher-than-average incidence of exhaust screen blockages (design error? user error?), and issues with the carb and fuel system. Here's something about the FS46 that I found on another site: "OK- FS 46's are pretty dependable units. 2 problems I'v repeatedly seen: 1. the fuel hose- if it is green its the good one. If its black replace it with p/n 4140-358-7702. Black hoses crack & suck air. Second issue: Zama carb. check valve problems. There are 3 nescessary tests for the C1U/C1Q series purge-type Zama carbs: you need a pressure & vacuum pump to test it. Step 1: attach pressure pump to fuel inlet & pump up to 6psi. If it holds pressure, the inlet needle is good, if not, needle or seat is leaking. Step 2: attach pressure pump to fuel purge outlet (line that dumps fuel back into the tank). Push the purge bulb a few times and see that it develops & holds a few psi pressure.Use the purge bulb, not the pressure pump to develop pressure. This tests the purge body & its check valves. Step 3: Attach your vacuum pump to the purge outlet and pull a vacuum- 7'' or 0.5mb. If it holds, all is well. If the vacuum gauge drops in less than 15-20 seconds, the main (nozzle) check valve is bad. Steps 1&2 can be fixed, failure of step 3 cannot- its new carb time. The ignition module is a possible problem, but on this series of trimmers, module problems are USUALLY confinded to "loss of spark when hot" issues. Good luck."

The line usually breaks because it is rubbing too hard against the other line on the spool and welds itself to that line. The flexing is then concentrated and it breaks at the welded point. You can minimize the problem by spraying the line with silicone, or teflon spray with it on the spool. The water trick also helps, but it dries out again pretty quickly. The best way to get rid of the breakage is to run at less than full throttle. I have found that the breakage will totally go away as you near half speed. I always use low speed when I am edgeing along chain link, rocks, or anything that the string hits hard, intermittently. For me, I needed to get a better trimmer to do the slow thing, as the cheap ones would not run decently, but my Echo and Stihl both do wonderfully at the lower speed, and also perform great at full speed in the regular grass areas.

I ended up buying a Stihl FS55R and promptly returned it the next day. Would not start at all.The dealer looked at the plug and found that it was bad from the factory (electrode broke off). Put new plug in. He then finally got it started and all it did was shake violently. He offered me either a new one or my money back. I took the money. I have a love/hate relationship with Stihl. My Stihl saw works great. I had considered an Echo or Deere but after reading several post here I bought the Stihl. When the Stihl equipment we have at work is actually working, they all run and start great. We do have a high break down rate though. To make a long story short I then bought a Husqvarna 223L and am very pleased. Started on the second pull out of the box and starts on either the first or second pull every time since (following the start procedure as the manual recommends). Good power and rpms as well. The older FS55R/C that we have at work runs like a scalded dog and starts on the second or third pull every time. I had hoped that the FS55R I bought would be similar.

I'm a professional landscaper and my two cents are: Our local Echo dealer is cheaper and easier to deal with than our huge local stihl dealer. That being said, my opinion is that echo weed wackers are the absolute worst choice, while the Stihl FS90R is the best weed wacker I've ever used outside of the old Shindaiwa before Echo took them over. Never liked echo weed wackers. We like to remove the guards and prefer the style where you can slide the guard up and down the shaft vs. being fixed. I've never used Stihl split shaft but am in the market. Used Echo and actually had decent luck with them. I like the fact that Stihl has carb screws still though!! I use my HT attachment and chainsaw attachment mostly. I would never use a weed wacker attachment just because I don't believe Echo makes a decent ww. After reading your analysis though, I think I'm going to stick w Echo split shaft vs. moving to Stihl. Though I am going to buy another FS90R!!