Best thing about Steel Egg was that despite being outnumbered aliens still took down a large crew of humans, novels like No Exit were much better written than it with much more interesting characters and plot but when it come to the aliens they screwed it up by having humans fight them with hands. And of course No Exit felt like it needed a few more chapters to end it properly.
DNA War had pretty much every aspect of it above average, one of my favorites alien novels overall.
Criminal Enterprise was too short and focused too little on the aliens, but in regards to the rest it was good.
Cauldron started quite interesting but developed quite average and had some annoying parts.