Consistent with my philosophy of perfecting as much as possible pre-shutter release, I maintain a sRGB workflow for nearly all files. I usually don't make any changes in colour, levels or contrast in
PS and hence don't need the wider gamut of aRGB; and I don't need the image degradation associated with unnecessary changes in colourspace.
Only those specifically prepared for home printing will I revert to an aRGB workflow to see them through. Those 'snapshots' destined for 6x4 bulk lab prints are done in sRGB too - as the labs usually aren't colour managed and assume sRGB files, and their output colourspace are much more restrictive than even sRGB.
A point many don't know or don't consider, many monitors including mine cannot display much beyond the gamut of sRGB. The extended gamut afforded by aRGB predominantly in the green region cannot be seen, so really you're making blind changes when you do so in image manipulation software. Unless you have a high end CRT or Eizo/Ilyama/Lacie LCD with 10/14 bit gamma LUT (Hitachi 25, 37 or 50ms S-IPS panels) your monitor cannot display colours much beyond the sRGB colourspace adequately - and this has nothing to do with calibration, it's simply beyond the scope of rendering for the display.