There are a lot of Lincoln biographies out there, and some of them are probably pretty good. Since this is the only one I've read, I can't really compare it to all the others.
However, Ronald C. White's A. Lincoln was a fascinating read, that really brought Lincoln and his time to life for me. In his book, White focuses on Lincoln's words (of which there are many) to understand a complex man who dealt with a complex problem. White strikes an excellent balance; he lets Lincoln speak for himself, but also gives enough context and analysis to give the reader a good understanding of the circumstance and the consequences that followed. It doesn't hurt that Lincoln himself is an interesting man and that his times were definitely interesting times. Such a work could become long and bogged down in details, but White never succumbs to that, either. Although the text is nearly 700 pages, it's all interesting, well-written stuff. I may not need to read another book on Lincoln after all!