I have been using Polish Pro since it's launch and still have no problems with it.
In fact I just did a little experiment on myself using PP and another product....I have grown my natural pinkie nails to an extra long length and they are now just over 2cm in just free edge length.
On one nail I did my fave PP colour and on the other nail I did the other product and just let them be to see how long they lasted before chipping, peeling, fading etc.
I finally got my first small chip on the PP nail last week and this was after nearly 8 weeks of growth.
Now I won't talk about the re-growth cause you can all guess what this would have been like
but I can happily say I had no chips until the 8 week mark and had no peeling, no fading, no cracking etc at all on the PP nail.
In this time I can also say that many times I accidentally bent my nail a few times and thought that would be the end of it but it didn't cause any problems.
I actually still have it on there cause I haven't had time to remove it and it has not chipped any further, so I still just have this tiny chip in the middle of the F/E.
So it baffles me when I see other PP users having so many problems and I try and help if I can cause I've had so much success with it on all my natural nail clients and myself.
You are right in the way of saying that you are new and this might be a bit of the problem as these things can take time to master and by the sounds of what you say, you are doing your application correctly by only capping the base and top coats.
The one big problem that causes chipping is pooling at the tip of the F/E and this might be the cause of your chipping problems. Really try to make sure there is not a build up of product before curing and check it after curing as well.
Be extra careful with your base and top coat, especially the top coat and make sure you are covering your color layers correctly and thoroughly and you are capping correctly and again, not leaving a pool of top coat behind.
Are you using a decent 4 bulb 36w UV light? or are you using one bought from China on Ebay? If you are using a cheapo one, then there's a big culprit. You are using only UV, not LED? PP is not made for LED.
The next question is, are you using the correct prep products? Are you using all NSI products or are you mixing up brands? Are you dehydrating and cleansing the nails correctly with Nail Pure and Cleanse?
When you do your first application, ensure you thoroughly clean the entire nail right down to the F/E and this includes when doing your cuticle removing step as the nail growth can (and does) pull that dead skin all the way down to the tip of the F/E but many techs don't do this step but I can assure you, it pays off to be thorough with this step. Are you using Vanish from NSI to do your cuticle removal step? are you cleaning it off correctly?
There can be so many variable as to why things go wrong and many people are quick to blame the product instead of looking at making sure the prep/application/curing/removal process is done totally correctly.
Maybe think about the things I've mentioned and see if there is anywhere you could improve on and see if it makes a difference.