First of all, Jay, I want to be clear that I'm still new at this and don't really have a lot of experience with all of the khukuris I've acquired. I have used each one to chop through 3-4" seasoned Norway maple limbs that a neighbor has in his "to burn" pile. I'm not counting the strokes but am trying to get a comparative feel as to how they perform. I haven't done it with the Kobras I have because one is pretty small and the other I have relegated to clearing out weeds. I'm also still learning about technique of both holding the khukuri and how to strike with it. I also interject second hand information, as best as I can remember it, from other forumites input-especially from the archives that I am in the process of going through. With these caveats I will try to address your concerns. I hope that there will be others that will jump in, too, since I know that there are many others on the forum that have more experience and can help round out your information.
Basically, yes, the Ang Kholas are the best choppers. The bigger they are, the better they chop. Also, the bigger they are, the more they weigh. The chiruwas, both the 16.5" and the Super CAK (SCAK), at around 20" I believe, perform as well as their standard handled counterparts. Once again, the chiruwa handle is only a little tougher than the tang through standard handle, it "may" transmit more vibration to your hand and I've experienced grey on my hand after using them due to the contact of the tang to my skin. Some people fervently believe that others such as the M43 and the 18th Century models will chop as well as a comparably sized AK and they are probably right. These forward curved models are slightly different than the shouldered AK as to connecting the "sweet spot" and some adjustment to your swing may be needed to bring it to AK level. The Ganga Ram Special also does a fine job of chopping, and some feel it does a better job of felling than an AK, and I am ready to agree with Yvsa that it strikes truer to where I want it to go than an AK. Speaking of Yvsa, his Yvsa Cherokee Special (YCS) is chopper along the lines of the baby GRS. Personally, my best chopper is a Hanuman AK that I have. Uncle Bill called the Hanuman blade a "full Ang Khola" with its two fullers. If it is nothing but a steady day of chopping ahead I would reach for it and probably bring the baby GRS along for a change up and possible limbing. There are also others that feel that the WWII model will do some a good job of chopping and is an excellent all purpose khukuri. (There is an 18" chiruwa WWII on the Exchange forum that I've been watching and just can't seem to decide about it yet.) As a personal aside, I feel that my 18" Gelbu Special chops almost as well at my 16.5" CAK and due to its lighter weight and blade shape could probably do some other things better.
If you are trying to decide which model will be your first khukuri, then first go for the one that connects with you the most (the one saying "Pick Me") and I'm sure you'll be happy. I'm sure you'll expand from there. But if you have a particular future use for your first khuk, it is best to define that use and ask for input based on that. For instance, if you're going to be chopping and splitting wood at home then a 20" AK or CAK is probably what you are looking for. But if you're looking for a general camping blade then the 3-4 pounds may be a bit heavy for packing or extended carry.
Starting to get a little bleary-eyed here so its about time to sign off for the night. I hope I've been able to be of some help and I'm sure you'll get more from others as they check out the posts. Keep throwing any questions you may have out here 'cause there's a wealth of information and lots of good people willing to share it.
Rick
