Yes and no Cid. Atlas flex track is probably cheaper than bulk rail, others certainly aren't. Atlas (I'm talking HO here, don't know about N scale products) makes code 100 and code 83. The code 100 (to me) isn't worth considering for handlaying. Their code 83 is .083 high, but is larger in cross section than other code 83 rail. The visual difference is striking. This is why Atlas can use the same rail joiners for both codes. Those joiners swim on correct code 83 rail.
So, yes it may be feasible to buy Atlas code 83 flex track and use the rail to handlay, but the appearance won't be as nice as it could've been. Myself, I would just use the Atlas track as is rather than put the effort of stripping the rail off and spiking it on wood ties. If you wanted to lay a turnout and have its rails match the flex track, then that would be a good use for doing so.
For what its worth, here is my opinion on track options available.
Atlas code 100, good for hidden staging tracks
Atlas code 83, acceptable for visable trackage, but rather large spikehead details. Shinohara and another brand I can't recall the name of, code 70 and 83, looks great, sucks to work with. Also very pricey. Handlaid, I love handlaying and its costs, especially turnouts, are as low as you can get. However, I miss the sight of tieplate details.
It's just a matter of what's most important to you.