If whittling and fine cutting tasks are a great consideration, and you don't have a habit of sending knives in for heavy re-grinds, then the Randall Model 18 has the thinnest edge at 0.020". That alone makes it the one to get for a fine tasks user that can also chop. Most hollow handles, even many expensive ones, for some reason, are on the thick side at the edge, and at the low price range you mention the Boker Apparo is very thick and will not whittle as is: It must be around 0.070"+(!)... I heard the Schrade was very thick at the edge, and note it is also much thinner in the blade overall than the Chris Reeves versions, so not comparable at all in quality... Chris Reeves are not bad in the edge at 0.040", but they grow a bit thicker towards the point...
Of note is the Model 18 does not have the deepest handle cavity, but it does have the greatest inner compartment diameter: Diameter is a much bigger plus than depth. Chris Reeves are only about 1 mm or so narrower in diameter, yet the difference seems absolutely huge...
There is a much cheaper alternative in the $50-100 range: It is to look on Ebay for "Parker" survival knives: These have a black-painted cast aluminium handles, usually ergonomically shaped with various blade shapes, and are cast/epoxied on the tang, so they are almost indestructible. Most Parker hollow handle knives, even with "normal" tube handles, are sound in construction and will not break. Their sheaths are decent leather, although the snap strap does not hold tight usually... They are at least 30 years old, and can look in rough shape... The edges are not ridiculously thick but not as good as Randalls. I remember mine in the 80s as hard to get a good edge on, but that applied to all my knives back then...
Gaston