I ran into this same issue with my Echo Timberwolf this weekend, cutting on the property. I'm going to research what options, if any, can get me longer, paired, dogs on the CS-590.
On another note, I never did admit that I bought myself a father's day present this year. I found a 500i on sale so it made quick work of the trees we cut this past weekend. I ran a 28" bar on it for a while which really saved my back, and then put the 20" bar on it which was plenty for the trees we were cutting. With a 20 on it, that thing screams through 15" pines like they are branches!!!
I'm still not that happy with getting the 500i started. Not sure why, but it takes quite a few false starts before it adjusts and idles. Once it is started, never another problem, but even after priming, it just does not want to start and idle. I'll read up on it and see if I'm doing something wrong, but for a saw that expensive, it seems like it should be easier to get going.
We ended up, between the 4 of us cutting this weekend, taking out 70 or 80 trees! We also got my RV trailer moved further up the hill closer to my new well, and got the storage trailer and Solar system moved up the hill as well. Views are incredible with all of the trees taken out, and will only improve more with the remaining trees that are marked.