I own a Ruger Mk. II and a Buck Mark. I've shot my uncle's Woodsman and a friend's Hi-Standard.
Field stripping the Mk. I is no problem... unless you're a crybaby who expects every gun to come apart like a combat auto. You do have to read the manual or have good directions from elsewhere. There are a couple points where gravity plays a role, but it is not difficult.
The same people who criticize the Ruger design and go on to praise the Buck Mark are neglecting to mention that on the Buck Mark, the sight rail must come off every time the gun is field stripped, and an allen wrench is needed to field strip it. (a new Ruger will need a tool to pry up the take-down lever and a mallet, if the gun hasn't been apart much) To me, the Ruger is a superior design, because throughout the whole take-down process, the sights stay aligned; they are attached to the elegant tubular barrel/receiver, which is one integral piece.
The Browning instructions say not to field strip the gun. Just clean it as best we can by opening the slide. When it gets so dirty it jams, we are instructed to bring it to a gunsmith. I don't know about you, but that is completely unacceptable to me.
On the plus side for the Buck Mark is that the trigger from the factory is better. Lighter, and with less overtravel. Not a huge difference, but it is worth mentioning.
The Mk. I has no last shot bolt hold-open, and the magazine release is at the bottom of the grip. You can't really have any fantasies about this being a tactical gun. But it sounds like you're grounded in the reality of it being a target gun.
The Woodsman is collectible, and you might have troubles finding a way to mount an adjustable sight, if it doesn't already have one.
Hi Standards were real live target guns, but the company's gone now, so parts might be an issue at some point.
In the end, I'd go with the Ruger. It has a great combination of:
- Classic design: this gun is a huge part of why Ruger is a successful company these days
- Aftermarket and factory support is still existing, even though it is a 60 or 70 year old design now. You can easily improve the trigger and sights if you want to.
Does this particular Mk. I have adjustable sights? If you get them on the gun to start with, it will save you a chunk of change in the near future. You can't do any serious target shooting with fixed sights.
If you're not a sentimental person at all, the Buck Mark is a good gun. It just doesn't have much historical value, as its design is kind of a combination of guns that preceded it. (Hi-Standard, Woodsman)
My Mk. II was my first gun purchase when I turned 21 back in 1997. I still shoot it regularly.
You can see the Mk. II and Buck Mark in the top row of this pic:
Last of all, it sounds like your father is planning towards the Mk. I, and it is best not to be choosy about one's gifts. They're all good guns, after all.