I have purchased some (summer) infantry from all lines and will do some comparisons.
First up is the 20mm Lahti AT Rifle, from left to right, LE, Bf & RR.
As you can see they do differ at bit in size, actually the LE one is scale-wise the best (just a bit to large) while the Bf one is somewhat to small, while the RR one is puny.
(No wonder that the Finns called the gun “Norsupyssy”, [elephant gun].)
You can also see my main issues with the RR and LE ranges, the LE has problems with to long limbs and the RR is over-sized (not so evident here though) and have overlarge bags and gear.