Where are you located? I'm ready to sell my beloved Echo 510 EVL, discussed many times on this forum. It's likely the most reliable saw I've ever owned, but I hate two things about it:
1. Older chain brake lever design, works great, but just annoying to me after using the Stihl's.
2. Smaller top-mounted filler necks are hard to fill from 1 gallon bar lube jugs.
In any case, if those things don't bother you, the 510 EVL would be a much better firewood saw than that little CS-310, IMO.
I am in Kansas City....If you think it still has plenty of life left in it feel free to msg me all the details!!
Thank you!
Don