Well, just comparing the first page of the English-Chinese half of the Yuan & Church with that of the Langenscheidt bilingual dictionary (which I would consider a better dictionary for travel purposes), at 'about' there's the useful phrase
What's it ~ ? (
book, film) jiang3shen2mede? in the Langenscheidt, but only
a book about China yi4ben3
guan1yu2 Zhong1guo2 de shu1* in the Yuan & Church (the C-E half of either dictionary meanwhile is inconclusive/uninformative at both jiang3 and guan1(yu2) with regard to using either phrase in questions relating to plots for example); then, there's both 'abnormal' and 'normal' in the Langenscheidt's E-C half (and corresponding entries in its C-E half), but only 'normal' (and its corresponding entry in the C-E half) in the Yuan & Church.
Sure, the "omission" in the Yuan & Church of 'abnormal' < > bu2zheng4chang2 isn't an insurmountable problem for anyone with an elementary knowledge of Chinese (i.e. how to negate linguistic items), but it is a slight inconvenience, and the Langenscheidt lists
hundreds of bu... entries whilst the Yuan & Church manages only two dozen (you never know, there might be people who'd want to learn and/or be "absolutely sure of" a few negatives at once), and it again allows quicker checking due to the doubling up i.e. having not only the unmarked positive entries but their negated counterparts allows look up at either.
Then, there are items (drawing on the Langenscheidt appendix of mainland PRC versus Taiwanese usages, though the mainland ones all appear in the dictionary proper too) such as
DVD (shu4zi4 shi4pin2 guang1pan2/ shu4wei4 xian3shi4 guang1die2) and
Band-Aid (TM LOL)/adhesive plaster (now apparently not the good ol' xiang4pi2gao1 "rubber ointment" of the OPCD, but rather chuang4ke3tie4/OK beng4) that simply do not appear in the Yuan & Church. So the Langenscheidt is a great dictionary, in the words of the editors "rich in sense distinctions" such as "is the
mouse you need for your computer...the same in Chinese as the
mouse you don't want in your house?". (Again, the Yuan & Church lack the computer term, but the Langenscheidt provides not only the PRC term but also the Taiwanese equivalent...not that the character for mouse doesn't appear as one half of each regional bisyllabic compound, or that one couldn't mime the object and its use in say a computer store! The OPCD has the PRC term, by the way).
The only "problem" however with the Langenscheidt is that, like the ABC dictionaries, it is completely alphabetized by Pinyin, which can take a bit of getting used to for those who've previously had only "first character('s Pinyin) in compound"-sorted dictionaries like the Yuan & Church (though the OPCD has the more prototypical presentation of this time-honoured type of sort order). For example, -an... compounds (in Pinyin-characterS) in the ABC and Langenscheidt get interrupted by -ang... ones, which can get tiring as the size of the dictionary and thus the list of items gets longer. But generally completely-Pinyinized ordering is the quickest look-up if you know at least the rough pronounciation (whereas with "first-character sort", you need to get not only the tone right but will also find it helps to know and look for what the first stroke of the character is, especially in those sections such as 'shi', or 'yi' etc! That is, dictionaries like the OPCD assume a greater familiarity with characters than may be the case with the average user in a hurry).
Anyway, if you're thinking of buying another dictionary, the OPCD isn't bad 'cos at least it's two-way (E-C/C-E), but you might like to consider the
ABC Comprehensive Chinese-English Dictionary for a great one-way bilingual, and the
Far East Chinese-English Dictionary (Simplified Character edition**) isn't bad either (beware the Pinyin-ordered spin-off rather than original Kangxi radical-ordered edition however, as I believe the Pinyin-ordered effort is only about half the size).
Heh, sorry to go on again, but I do enjoy using and comparing dictionaries, and assume that at least some of what I'm saying will be of interest!
*The very same example appears in the OPCD, IIRC in the C-E section at guan1(yu2).
**The words SC should perhaps be in scare quotes (thus: "Simplified Character" edition) because although the main entries indeed supply the simplified form alongside the traditional for any given character (where such a difference exists), the dictionary's
indices (by radical, or by total stroke count) only deal in traditional forms (wed to a Kangxi arrangement), thus making it impossible to look up non-trivial (e.g. having more than just something like the simpler 2-stroke rather than traditional 7-stroke left-side "speech" radical) simplified characters on the basis of their graphic form. For example, one will search in vain in this radical index for the simplified 2-stroke "cliff" radical-resembling form of, and thus character number/entry for, chang3 'factory' - only the traditional 15-stroke form is to be found, and then only under the 3-stroke "broad roof" radical.