Having never used LPC myself I'm not really qualified to make a comparison between that and Smaug. I would assume the softcoding support available in any LPC based engine would make it more versatile than something more rigid like Smaug.
However, Smaug is one of the better Diku based branches to work from. The FUSS project has been keeping things nicely maintained now for several years with a fairly active community behind it. From time to time I even get communications from official Smaug developers who are apparently still keeping track of where we've taken things since the last official Smaug release in 1998.
I didn't want to just let this topic seem like it's been ignored either. I have a feeling that most folks who frequent this particular site are not very familiar with LPC and are in the same boat I am as far as making comparisons between it and Smaug. Personally I think if you're looking to give a Diku codebase a try, this would be the best choice for something stable and well maintained. If you're looking for something that's also fairly advanced with several additional features, you might give AFKMud a look as well.