Only for you Liver Eatin Johnson!
As you know, I haven't built a Chambers "kit" however I have built over 13 Pecatonicas so I can't really compair them based on what comes in the box.
I did a little research though and came to this conclusion:
If you want one of the 10 different styles offered by Chambers which includes the York, Lancaster, English sporting or smoothbore and Christian Spring plus a few others then Jim Chambers is a possible option.
If your tastes run towards another style of stock then Pecatonica River's selections of over 33 different styles are very much worth considering.
These include Reading, Bedford, Buck, Beck, Leman (half and full stock), Hawken (half and full stock), Ohio and over 5 different Southern styles.
The costs for the Jim Chambers seems to be around $850 while Pecatonicas are around $560.
I don't know if you can get a "custom" kit from Jim Chambers but you can from Pecatonica.
What do I mean by custom kit?
If you don't like the lock offered by Pecatonica for instance, you can ask that they supply the stock without the lock inlet. This permits you to inlet the wood for the lock you want to use.
The Pecatonica River stocks are usually not cut for the buttplate. This allows you to install it with the length of pull you want.
The Chambers guns stocks all have 1/4 inch cast built into them while Pecatonica River stocks do not.
I don't know what type of Curly Maple the Chambers kits supply. I do know that most of the Pecatonica stocks are made using the soft Curly Maple (which often has better curl although it isn't quite as easy to get really sharp carvings. (I might add here that soft maple is still harder than walnut).
When all is said and done, I am sure both companys produce excellent kits. I know I have never been disappointed with Pecatonica Rivers parts.
Zonie