Tom, don't know if this helps, but there were at least two good Calvinists who thought an Armenian could be a true believer. Actually, I guess that would be three, including Ryle who I think was Calvinist leaning.

Nothing could be a more weighty testimony against narrow-mindedness than his request, made shortly before his death, that, when he did died, John Wesley should be asked to preach his funeral sermon. Wesley and he had long ceased to agree about Calvinistic points; but Whitefield, to the very last, was determined to forget minor differences, and to regard Wesley as Calvin did Luther, "only as a good servant of Jesus Christ." On another occasion a censorious professor of religion asked him "whether he thought they would see John Wesley in heaven?" "No, sir," was the striking answer; "He will be so near the throne, and we shall be at such a distance, that we shall hardly get a sight of him!" - from J.C. Ryle's short sketch of George Whitefield

“Most atrocious things have been spoken about the character and spiritualcondition of John Wesley, the modern prince of Arminians. I can only sayconcerning him that, while I detest many of the doctrines which hepreached, yet for the man himself I have a reverence second to no Wesleyan; and if there were wanted two apostles to be added to the number of the twelve, I do not believe that there could be found two men more fit to be so added than George Whitefield and John Wesley.” - Spurgeon