Are you sure you meet the qualifications to purchase one in the first place?
I can handle the saw with no problem, I have a 362 witch is in the sane power range of the 391
Ms 391 specs.
MS 391 Specifications - Mid-Range Use
DISPLACEMENT 64.1 cc (3.9 cu. in.)
ENGINE POWER 3.3 kW (4.4 bhp)
POWERHEAD WEIGHT 6.2 kg (13.67 Ibs.)
FUEL CAPACITY 600 cc (20.3 oz.)
CHAIN OIL CAPACITY 350 cc (11.8 oz.)
OILOMATIC® CHAIN 3/8" RS3
GUIDE BAR LENGTHS* (Recommended ranges) 40 to 50 cm (16" to 20")
STIHL ROLLOMATIC®
POWER SOURCE Gas
Specs i=on the ms 362.
DISPLACEMENT 59.0 cc (3.6 cu. in.)
ENGINE POWER 3.4 kW (4.6 bhp)
POWERHEAD WEIGHT 6.2 kg (13.7 lbs.)
FUEL CAPACITY 600 cc (20.3 oz.)
CHAIN OIL CAPACITY 325 cc (11.0 oz.)
OILOMATIC® CHAIN 3/8" RS3
GUIDE BAR LENGTHS* (Recommended ranges) 40 to 63 cm (16" to 25")
POWER SOURCE Gas
The 391 is a farm & ranch saw. But if you compare the specs with the 362
There almost identical.
No mention why the pro saw is worth the extra money.