Huh? What context are you using when you say "cheap"? Build quality or value?
I like talking "torque" and 60 cc saws. I like talking value as well so here goes:
Almost spent a grand on an ms 400 when I started my tree service company. Went 620pw instead: $592 with 27" bar and 2 chains. Later got a back-up cs 590, but ran the sht out of it this season! Made thousands of dollars off that darn 590-box-store-thing!. So BOTH saws were the price of a single ms 400.
But back to the 620pw vs 400:
620pw: over oils a 28" bar
400: can barely oil a 24" bar, gotta spend more money to get a proper oiler
620pw: phenomenal aluminum wrap handle.
400 plastic.
620pw: set of felling spikes
400: single felling spike (pathetic).
Could care less about the weight difference. A redesign will do stihl some good.
Dunno this dude, but a good unbiased comparison:
Cutting speed, that 620 torque and filthy-good oiler, 620 catches up and slapped the 400 in the big stuff: