I would respectively disagree - the Chinese have been doing some amazing things with crystal efficiency lately!
For example, the recent research here on the new DX modules -
we are seeing efficiencies > 20% on the 100mw units, and up to / exceeding 25% on the 200mw models!
For instance, Hemlock_Mike's 200mw unit, being pumped by an over-driven 500mw 9mm 808, input current to the driver of only 610ma, metered green output of 160mw!
That would be at / likely above 25%!
Or an even better example, Bob_Bryce's recent work in pot-modding DX True 5's. One of the units had poor output due to mis-aligned crystals, and he had the foresight to meter the 808 LD directly before replacing and re-aligning the crystals. The result? 299ma in, 76mw metered green out!

The best part? The 808 LD was metered at 252mw output!
That's an efficiency of over 30%!!! :gj:
And lest you argue that it was a "freak" result due to his god-like alignment skills

(although I got to admit, anybody who talks about hand re-aligning DPSS crystals like it was normal maintenance like mowing the lawn or something, impressed the
hell out of me!

), I would also point-out that two other identical units (whose alignment was left untouched), also set to 299ma in, were also metered at 77mw & 72mw of green!!!
So to answer the OP's question,
yes, 25% is certainly possible!
But on the flip side, my own recent experience with O-Like has been less than stellar (review to follow when I get around to it). And recent metered tests of their 200mw module has indicated that some were doing noticeably less than that, with someone commenting it didn't seem to be any different than their 150mw unit!
So I would exercise
extreme caution, particularly given that $800 price!