Just about any mill with a MT or R8 taper will take screwed shank cutters with a suitable holder. However a more useful, cost effective and versatile system would be to get an ER collet holder and build up a range of collets. These will hold screwed, plain and Weldon shank cutters as well as many other things like drill bits, reamers, etc. Screwed shank cutters are becoming less common, take a look at the lines of Dormer and maybe only 1% of their range now has screwed shanks.
Of the two you mention the ARC SX2PG is the more recent model wth the twin gas struts so should be better to use.