Pipe vises in general do not seem to command very high prices. Your No. 1 does have a couple things going for it though. Most Yolk clamp type pipe vises bolt directly to a bench. Yours looks like it has pipe sockets for setting it on the ground in the field. Also that extension socket to a V rest on the back side with its own pipe mounting feet is not common. Most vises on pipe legs are tri-stands. Not sure how much of a premium that adds but I'd pick it up for $25 or so....but then I'm a sucker for things I haven't seen before.