To my mind, they look too wide, given that it's a single-breasted jacket. But then, I like quite narrow lapels in general. The only peaked lapel dinner jacket that I have ever owned was inherited from my father, who bought it from Harrods during the 1950s. It's double-breasted, and the lapel width is about two-thirds of that in the picture that you showed. You don't give any indication of how broad you are - I think that if you are quite thick-set (for instance like a linebacker or prop forward), then you can do a wide lapel. If you are thin, I would advise against it, although having said that, there are plenty of 20th-century dandies (eg Fred Astaire) who could get away with broad lapels, despite being thin. I hope this helps - ultimately, you have to decide what sort of look you want to achieve. This is why I will never buy a suit on Ebay, because it seems to me that it's not possible to judge how it will look. I would rather pay the extra, and see it in the "flesh".