I have them and have played a couple of games. They are not bad, but have some grey areas and odd features. Melees go on for ages, which apparently is what the author intended, but doesn’t match many historical accounts. I asked the author about several things which I found unclear, and his response was “Well, you have certainly found lots of things not covered by the rules”, but he didn’t actually address any of them.
So a bit mixed; you would be welcome to my copy for the cost of postage; maybe you will find them better than I did.
These days I use “For King and Parliament”