I just noted how different these requests come off. Ultimately, it doesn’t seem to effect my final decision about reviewing, but it does effect my initial reaction.
Journal #1 Request
Dear [Potential Reviewer]
We are writing to ask if you’d be interested in reviewing a manuscript for [Journal] entitled [Article Name]. Based on your expertise, we feel that you would provide a thoughtful assessment of the manuscript’s strengths and weaknesses.
We hope that you agree to review this paper, in which case you will receive another email with instructions for accessing the manuscript using our on-line review system. We would need this review returned within [time frame]. If you are unable to review for us at this time, we would appreciate receiving names of other potential reviewers you would recommend. In order to expedite the review process, we ask that you please respond to this request within the next 2-3 days.
Journal #2 Request:
Dear [Potential Review]
We would appreciate your review of this manuscript, which has been submitted to [Journal]. We ask that you return your report within [time frame]
Thank you for your help.
Maybe some people like short and to the point?