Continuous upholstery nail studs are intended to speed up and simplify the work of fitting decorative nails particularly where straight lengths are involved.  Continuous trim is not intended to go round very tight curves.  Loose nails are for that.  However slight curves may be accommodated by carefully bending (or fractionally notching) the short length of metal between false nail heads.  Care needs to be taken to do this.  For the amateur it is important that the strip be 'walked' around the job before any nailing takes place.  This is to decide the most appropriate place for joins and even more importantly to avoid a 'nail head' appearing on a sharp corner where the nail strip is to be bent.  Use the small metal strip between nail heads for that.  Planning and thinking about the job to avoid nail heads being smack in the middle of a corner will save endless problems.  Careful spacing of spare loose nails will accommodate any slight length issues without affecting the appearance. Extra nails are available to be ordered in small quantities for this purpose. Locating a nail at each end of the nail strip and one near the centre of the strip to ensure the nail strip is in exactly the right place and is straight and level before doing the final nailing will produce a really professional looking job.  Continuous trim is potentially easliy damaged during cartage so great care is taken in getting the long strips packaged safely and securely which has a bearing on the price.