Speaking from Team Pro experience:
- A really old and swaybacked one is a delight, especially if it had the "pre-softened" leather. One of mine dates from 1967 (technically it's a Brooks Professional, with slightly smaller copper rivets and a cut-off nose, but same width) and someone else did the hard work for me.
of the new ones:
- The Ti railed one is completely different in feel. The leather doesn't have to break in as much because the rails are so flexible compared to steel; remember, they have to be the same diameter to fit the seatpost, but Ti is only about half as stiff (the longevity is probably less too, because I doubt all that flexing is within its fatigue limit). More likely to be comfortable from new.
- The steel one has no "give" and is like granite when new; the Team Pro is reputed to have the thickest leather of any Brooks saddle. Mine is visibly broken in after 1000 miles and is reasonably comfortable, but it needs another 1000 on it.
For a cheap fit, ride and forget saddle, the Specialized BG Comp 143 suited me perfectly. On a very long summer ride it won't breathe like a leather saddle, but it is a very good shape.