Being an iPhone programmer, we also have this dilemma; should we use code or xib resource file to create a view? We have to choose between performance and ease of maintenance. Now we have another solution:

http://d.hatena.ne.jp/KishikawaKatsumi/20090427

This will convert an xib file into a objective C file, that you can insert the converted code into the loadView method of the view controller. So that we can design our views using interface builder and than convert the view to code for best performance.