The liners with grit in them are a bit more resistant to roller issues, but the amount of grit is very sensitive to how thick the coat is. Most liner products are hard to roll consistently, as the wetness of the roller, the direction, and the force on the roller, all influence the outcome.
Otherwise full coverage can cause the texture to get weird in those areas.
You will usually want to roll, or at least use a color matched under-coat paint, on most of the hard to reach areas, around doors, gutters, windows etc. Test with about 40psi through your hose/gun first.
The shutz guns spray monstaliner decently well at lower flow rates, just make sure you are okay with the pattern.
