Echo CS-680 vs Stihl MS 391

Echo / Gas

Echo CS-680

60cc class

~$780

Stihl / Gas

60cc class

~$840

The Echo CS-680 costs about $60 less; the Echo CS-680 has more engine (66.8cc); the Echo CS-680 swings a longer bar (20 in).

Spec	Echo CS-680	Stihl MS 391
Approx. price	~$780with 20" bar and chain	~$840with 18" bar and chain
Engine class	60cc classby displacement	60cc classby displacement
Power type	Gas	Gas
Use case	Professional	Farm & Ranch
Engine	66.8 cc	64.1 cc
Rated power	—	3.3 kW
Bar length	20 in	18 in
Single-pass cut	about 18 in	about 16 in
Bar range	20-27 in	16-25 in
Chain	3/8" pitch / .050" gauge (PowerMatch bar, rim sprocket)	3/8" pitch / .050" gauge (33 RS3)
Weight	14.6 lbpowerhead only (dry, without bar and chain)	13.8 lbpowerhead only, without fuel (16.7 lb with the 18" bar and chain)
Warranty	5-year consumer / 1-year commercial	1-year consumer / 3-month professional (Stihl policy effective Jan 1, 2026)

Tinted cells mark the better figure on that row alone: more engine, longer bar, lighter, cheaper. A lighter weight is only a win on the same basis.

66.8cc with a low, torquey power delivery owners describe as built like saws used to be
Adjustable oiler with a manual override — genuinely useful running long bars in dry hardwood
Rim sprocket, aluminium handle with rubber grip and PowerMatch bar are proper pro-grade parts
Top-mounted tool-less air filter cover keeps in-field servicing quick
Takes bars up to 27 inches, covering real felling work
5-year consumer warranty on a saw in this class

Owners who have run both say the lighter CS-620P out-cuts it with anything under a 24-inch bar
14.6 lb powerhead and a slow-revving character make it tiring next to modern 70cc saws
Plastic sprocket cover where the cheaper CS-620P gets magnesium
An older design that Echo has not refreshed alongside the X Series saws
$779.99-$799.99 puts it above the CS-620P with no clear advantage below a 24-inch bar

Biggest engine in Stihl's farm range — 3.3 kW handles a 25" bar and large-diameter felling
Owners report ten-year service lives in homeowner use
IntelliCarb and pre-separation filtration hold mixture steady as the filter loads
Bumper spikes, side-access tensioner and toolless caps — easy to work around in the field
About $270 less than an MS 362 C-M while out-displacing it

Glued transfer-port covers are a documented long-term air-leak path, and owners report piston destruction when one lets go
13.8 lb powerhead — heavier than the pro MS 362 C-M, which makes more power
Long-term users describe it as awkward to work on compared with the pro chassis saws
Does not hold up under commercial use; owners who cut for pay move to the 362 or 400
No M-Tronic at $840