The original FT-5 (v1) was a dated design for sure, but it was a great platform to build upon.
The v2 design was a tremendous improvement over the v1 (IMHO), with a great deal of the credit going to this site's owner/moderator Chris.
That being said, I agree with @Tin_Falcon that there are other viable options out there that are worthy of serious consideration these days.
However, you could do a lot worse than starting from the basic FT-5 platform/desgn for whatever ultimate goal you have in mind.
That was the approach that a lot of us have taken, and I would venture a guess that there are probability very few completely "stock" FT-5's left in existence, all the rest having been upgraded or modded in some manner.
But I did see a (claimed) new-in-box unbuilt FT-5v2 kit on Craigslist locally only a few months ago.
It is long gone now, but I was utterly amazed that I even saw it.
The FT-5 is still a darned good printer 
and I use mine several times a week on average (mixed home and business usage).
It is a real workhorse and I am very, very glad to have it.
Thanks John (and Chris..!) for a nice, robust design.
