I suppose I tried too hard to keep a post short, leaving the wrong impression. I posted that link in #3 as what I think is a short introduction to why HRM ought to be avoided. I've never had personal experience with A HRM adherent, except online in debate, opposing their agenda.
I doubt it's good to lump all movements involving Judaism in with them, like some of the Messianic Jew congregations, of which there are many variations, some resembling the old Worldwide Church of God-Armstrong group, while others remind me of how it must have been for that soldier chained to Paul.
There are people I know are as Christian as Paul or Peter, or any of the most devout I personally, who have a Jewish background, who have embraced Jesus as Lord and savior. Two groups of them I am familiar with have members who are expert on everything Old Testament, cherishing every word, but also the New Testament. Both of them have their ministry focus on reaching Jews for Jesus, reaching gentiles along the way. Their manner is to prove the NT using the OT as much as will help. On Passover they celebrate that as a congregation, inviting gentiles to take part. Both conclude that by keeping the Lord's Supper, preaching the typology of scriptures for those ordinances. I had led in the Lord's Supper many times back home, but found I was doing so quite ignorantly, never hearing of the connection of the two.
Those two teach the whole Bible, but their work is to make disciples of Christ who understand the "whys and wherefores" of the entire background of what the apostles knew about Judaism and of Jesus. Such knowledge is powerful. It's why most Christian leaders and scholars have been in favor of keeping the OT bound to a NT volume in our Bibles.
The distinction I've observed from being around those people is they remain excited about the Lord 7 days a week, taking Jesus home with them, returning to church with Jesus. Their homes testify of Jesus, homes full of love, children remarkably obedient and pleasant. They all seemed very prosperous, healthy.
I never heard legalism from them. They all conclude with teachings centered on Jesus and his commandments, treasuring all the NT. They observe some Jewish feasts, but use those to teach the fulfillment in Christ. They meet on Saturdays and Sundays, Wednesdays, to accommodate people with different needs, and allow for times when a rancher just can't always leave home every Sunday. What they do would be very difficult to learn from modern books, and would require writing a book to explain this. So I am open to fellowship with Christian groups like theirs, but not the hardcore HRM into which the good Messianic groups are lumped. I wish I could be specific about where they are, but my clients are ranchers for whom I designed private lakes and still serve to update ecological management plans. I'll be visiting them every few years the rest of my useful life, enjoying living on their property, fellowshipping day and night. I know from them there are many more churches like theirs around the nation.
Sorry for the confusion.