Nescafe Espresso instant is purported to be the best of all instants by many people who have experimented with instant coffees, including the ones discussed above - this according to my research department. I think it is very hard to find except online, and it is expensive.
However, if you are a fan of light roast American style coffee this may not fit your tastes.
I'm in the process of ordering some. Now that we have a very preliminary solution to the JMT pencil I feel like I need a resolution of this issue as well.
I made some Aeropress coffee this morning and it was excellent, even to an espresso drinker. Using a few modded techniques and a good deal of force, the Aeropress can even make something sort of like espresso, but I would not personally feel these extra mod were worth it away from my home espresso machine.
Unfortunately the weight of the LW (car camping) kit for this, including Aeropress, mini Porlex hand grinder with porcelain bur, and battery operated Aerolatte mini milk frother is still around 16 oz.
I have verified the the press component from the Bodrum 4 cup french press and a host of other french presses and possibly the one you already have (about 94 mm in diameter) does perfectly fit the Jetboil and the SP 0.7L Ti mug.(2.7 oz). It also comes apart and would pack nicely. So if you are a french press fanatic with a Jetboil or the right sized mug already then this might be a high end solution for you. Should be much better than the crap one sold by Jetboil.
I think the above will probably become my solution for car camping and overnights that involve more navel gazing than hiking. Though I will continue to practice with cowboy coffe techniques to see if I can get a good enough brew to be worth it, probably I will be satisfied with one or another of the instants in the end for UL. I may even go back to the (objectively speaking admittedly foul) General Foods International Coffees, such as cafe Vienna. These have the advantage that the milk and sugar are already in there (sugar doesn't seem to taste so bad after hiking 20 miles) and this stuff can easily be found in every crappy supermarket and even in 7-11 type stores at the last moment. Buy, open, dump in ziplock baggies and you are gtg. One "box" of this is good, I have found, for 5-7 days.