Kent Rasmussen, gentleman he is, politely finds several problems (21st century =issues) with the Bradford Press Edition.  
In USA copyright law, everything published prior to 1922 is in the public domain (A 50 year EU standard would be more fair). Nevertheless, what makes a volume worth adding to a library would be the addition of editorial commentary, and for example, the value added of UC Press editions of the MTP are foremost in my mind together with the Oxford Edition published in the 1990s. With SLC / MT the illustrations of original publication are par and parcel to the written world, or at least provide for additional understanding.
Just like Arden or Norton editions of Shakespeare's plays, these academic additions are what add human value. For any self directed learner, they are the key to understanding the meanings of words uncommon enough to be in a dictionary such as the Webster's New Collegiate. These additional materials are the stuff that links are made of, awakening the trails of additional inquiry. 
Rather than settle for a pretty face, a gilded edge, find an edition with the added value of scholarship and add your own underlines, highlights and notes. Secondly, I always look for  editions that are of "acid-free" or other durable paper, good for 1 or 2 hundred years, when there may be few new books made of paper. Finally, think of a good home for your books at some future time when you can't yourself enjoy them.
Gordon Snedecor in Portland, OREGONtwitter.com/pdxgordon
> Date: Fri, 11 Oct 2013 18:47:56 -0700
> From: [log in to unmask]
> Subject: Bradford Press facsimile edition
> To: [log in to unmask]
> 
> BlankToday's mail brought an elaborate promotion for a 15-volume =
> collection of facsimile reprints of Mark Twain >books produced by the =
> Bradford Press of Morton Grove, Illinois. 

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