From the abstract of "Health and temperaments of cloned working dogs," a study published in the journal J Vet Sci:
Only about half of all trained dogs may qualify as working dogs through conventional breeding management because proper temperament and health are needed in addition to their innate scent detection ability. To overcome this low efficiency of breeding qualified working dogs, and to reduce the enormous costs of maintaining unqualified dogs, somatic cell nuclear transfer has been applied in the propagation of working dogs.
As the paper continues, the authors point to some specifics—dogs trained to work with military and armed forces, for example, as well as guide dogs. Using data exclusively from dog cloning experiments in South Korea, they demonstrate that more than 90% of trained working dog clones retained the necessary qualities — health, temperament, et cetera — to make them successful candidates for the same work. In other words, it's twice as easy (and almost a surefire success) to train a cloned guide dog or bomb-sniffing dog than it is to train a bred dog for the same work.
It's worth reiterating that this study is based on a small sample size of dogs that were cloned in South Korea. The authors also acknowledge that are x-factors and other complications in the cloning process that could affect their results as well. "There have been concerns about the health of cloned animals ever since the beginning of mammalian cloning," they concede, adding:
Normal and healthy cardiovascular function is important to working dogs, but there have been reports about abnormal cardiovascular function in other cloned animals, such as pulmonary hypertension and right-sided heart failure in cloned calves and sheep, and left- and right-sided heart abnormalities in cloned piglets. However, until now, there have been no reports on cardiovascular analyses of working dogs, although echocardiographic parameters of seven cloned beagles were within normal reference ranges, indicating normal anatomy and cardiac function.
The slightly higher birth weights of cloned working dogs […] compared to those of dogs produced naturally might be due to the lower average litter size in pregnancies derived by transfer of cloned embryos compared to pregnancies produced by artificial insemination; regardless, the cloned dogs showed normal growth patterns.
There are always ethical complications and concerns when it comes to both dog breeding, and cloning in general. Add some eugenics into the mix, and yeah, there's a lot going on here.
Health and temperaments of cloned working dogs [Min Jung Kim, Hyun Ju Oh, Sun Young Hwang, Tai Young Hur, Byeong Chun Lee / J Vet Sci]