Talk:Stalker/@comment-27069434-20180212074217

To sum them up:

1 Collect piles of metal debris for you in their creepwine nests - handy

2 Can be outrun somewhat easily even "on foot" if swimming in straight line, minor course alterations allowed - thus you can do "swim-by" to chop creepwines or pick off the seed pods unharmed, or circumvented at close range (kiting)

3 Can be temporarily driven off by a single knife cut - will flee for a few seconds at speed exceeding that of a player "on foot", but slow down shortly after the strike, can be caught up with and stabbed to death while kiting with relative ease, though retaliation is likely.

4 Reported to be tamable via feeding peepers (favorite) or other fish and thus even more useful as living defence/metal gathering mechanism/free swimming landscape decor (mind to clean up metal debris after them off your "lawn", though)

TL;DR - safe&useful, as long as you can leg it (even if swimming on your back)