The reason why people go through grandparent DNA testing is that they intend to establish the relationship of the tested child with a grandparent in question biologically. With grandparent DNA testing then there is a possibility that you can find out whether the alleged father and the grandparent share the same genetic composition. Given that the alleged father might not be present at the time when the DNA test is supposed to be carried out this is where grandparents DNA testing comes in. When going through this type of DNA testing you do not need to use both grandparents and one sample is in enough. The the grandparents DNA test is not in any way inaccurate and this means that once you order the DNA test kit you can be certain of the most accurate result. The accessibility of the grandparents DNA test is not a problem since it can always be accessed from an online store. It can be important that the mother of the child go through the DNA testing as well so that the results can be more accurate. In case the mother of the child cannot take part in the DNA testing due to unavoidable circumstances then what happens is that both the grandparents have their genetic samples tested so that it can be easy to determine the genetic profile of the alleged father. As long as you order for a DNA test kit from an online store then you can be certain that it is going to be shipped to you immediately. Given that the process is going to be very simple from the collection of the samples to get the reports this means that no time is actually wasted on the process.
If you have always wanted to obtain child support from the alleged father then you can use the DNA test to get the evidence for the same. However you should ensure that the father of the alleged child is aware that you are going through the DNA test so that the court can admit those results. There is no way the court can authorize DNA samples if they are considered illegal. In case you take the grandparent DNA test and it proves that the alleged father of the tested child is actually the biological father then the alleged father might be forced to take their own DNA test.
There is nothing which makes grandparents DNA testing the best other than the fact that it helps when dealing with parental rights question since it can determine the paternity of the tested child. It is worth noting that if there are any problems during inheritance than a grandparent DNA test is going to resolve the problem.