The validity of instruments appropriate for eliciting L1 (first language) and L2 (second language) speech act data has been widely debated. Over the past decade, in investigations devoted to establishing L2 learner's socio-pragmatic competence and performance, discourse completion tests (DCTs) hae become increasingly common as elicitation instruments for comparative analyses of native speaker (NS) and non-native speaker (NNS) socio-pragmatic behaviors. This paper addresses the issue of what can be learned about L2 speech acts from the data obtained by means of English language multiple choice (MC) and DCT instruments in two experiments. Specifically, the study focuses on the L1 responses of NSs and the L2 responses given by speakers of Chinese to MC questionnaires and DCTs dealing with the appropriateness of advice in common and observed situations. When responding to the MC questionnaire, NSs selected substantially fewer options with either direct or hedged advice than the Chinese subjects did, which is congruent with the body of research on NS and Chinese L1 pragmalinguistic behaviors. On the other hand, significantly more NSs than Chinese preferred direct and hedged advice in response to DCTs. From this perspective, DCTs may not be the best elicitation instrument for L1 and L2 data pertaining to ambiguous and situationally constrained pragmalinguistic acts.