The best quality kits come from <b>Berea</b> (they supply a lot of Woodcraft's stuff and Rocklers, too) and from <b>CSUSA</b>. My personal preference are the kits from Berea; from CSUSA I use mainly the Gents and Gents Jr kits. I like especially the kits using the thicker "B" mandrel from Berea. I have not heard too much good of Penn State Industries kits, but have not used any of them either to form my own opinion.
Berea is the leader when it comes to the different platings, they have Chromium and Black Chrome, upgrade gold, Titanium(gold)nitride and Black Titanium coatings, diverse colored satin finishes, Platinum, Rose gold and even massive Sterling silver hardware. Not for all kits, though, but a lot of their kits can be had in three or four different finishes.
Keep in mind that gold platings are not very long lasting on a pen that is used daily, it wears off within a short time, i.e several months. Therefore, if you want a superb quality (and when you start selling pens, you want your customers return because of the quality you offer) don't cut yourself short and use the cheaper kits. I even use for "simple" slimlines the Titaniumgold coatings (you can get quite some price breaks when you buy the kits in larger quantities, check the catalogs and web sites of suppliers for that and call them and ask for their best price!!). On the other hand, the chromium coatings are one of the cheapest and lasting very long, too.
Most of the suppliers offering one or two click pens, but what I have heard so far is not too good either, we are still waiting for a good quality click pen mechanism. Until then, I make none of them.
Rudy