Yes, peritoneal dialysis (PD) is definitely a cost-saver. And it can be a time-saver, as well, because you can schedule your PD runs around your work and social routines. If you can use an automated PD machine (AKA "cycler") while you sleep, then your entire day is freed up. Also, perhaps the number one advantage is that no needles are necessary.
Finally, it's much easier on the kidneys because it's a continuous therapy (multiple daily runs or an extended nightly run) compared to haemodialysis/hemodialysis (AKA "HD"; two to four runs per week; these short, high-volume runs are very tiring).
Having said that, there are disadvantages, as well. The most commonly-occurring one is that not every renal patient qualifies for PD because of a pre-existing medical condition. Patients with implanted devices (e.g. pacemaker, defibrillator, shunt, etc.) are often disqualified. Many patients who have had previous abdominal surgery may not be able to tolerate a catheter implantation because of built-up scar tissue or other internal issues.
After the catheter is placed, a whole new host of problems begins, The biggest problem is the constant danger of infection at the point where the catheter exits the body (mostly because it's hard to keep everything sterile down there). Peritonitis is a common occurrence due to the presence of the catheter, as well as the infusion of 2+ litres (more than half a gallon) of dialysate per run. Some patients have to perform as many as four runs per day. The potential for contamination is pretty high.
Other complaints that we heard were more about the practicality of PD, such as having to buy new clothes (unsurprisingly, the infusion of 2+ litres of fluid causes your waistline to expand quite a bit!) and having to store pallets of supplies (primarily dialysate) at one's residence.
Overall, though, PD does seem like the easier method and the patients seem happier to be on it than HD. Unfortunately, we noticed that a large portion of those who started on PD usually end up on HD after a few months due to the aforementioned infections and/or their kidneys need more intensive filtration than PD can provide. This probably explains why 89% of all dialysis patients around the world areon HD (see halfway down the page below Table 3): http://ndt.oxfordjournals.org/content/20/12/2587.long) (Yeah, it's a ten-year old paper. I couldn't find a newer source that was fully available on the web. However, the numbers are holding steady, according to the renal unit stats in my region.)
Frankly, I don't know why some countries (e.g. Mexico) have such high PD numbers. Without eventual haemofiltration, I suspect that their patients' life expectancy is shortened. Tragically, it probably has to do with cost.