I have no issues using ratcheting wrenches to break loose a fastener. They are not much different than a typical, multi-tooth pear head ratchet.
The Matco 88-tooth mechanism, Snap-on's Dual-80 mechanism...they are essentially the same way a modern-day ratcheting wrench works.
There are several manufacturers in Taiwan that are producing ratcheting wrenches, and they are not all equal.
KTC branded ratcheting wrenches have these figures:
8mm: 22ft-lb (30Nm)
10mm: 52ft-lb (71Nm)
12mm: 67ft-lb (91Nm)
14mm: 116ft-lb (158Nm)
17mm: 197ft-lb (267Nm)
19mm: 238ft-lb (323Nm)
For Kabo-made ratcheting wrenches:
Requirement as per ANSI on a 24mm ratcheting wrench is 376ftlb. Kabo withstood up to 488ftlb or 67kg
Kabo's 72-tooth, 16mm wrench beam started to bend at 253ft-lb. Attached picture is at 290ft-lb. The gears were still fine (gears would break at 144ft-lb for competition).
Here's an independant test (from 2007):
SEK offers these: