EXHIBIT 16 "LETTER OF FORMER ACCOUNTANTS" 4 [LETTERHEAD OF FELDMAN RADIN & CO., P.C. CERTIFIED PUBLIC ACCOUNTANTS] July 31, 1997 Securities and Exchange Commission 450 Fifth Street, N.W. Washington, D.C. 20549 Ladies and Gentlemen: We have read the statements made by Proformix Systems, Inc. (formerly Whitestone Industries, Inc.), which we understand will be filed with the Securities and Exchange Commission, pursuant to Item 4 of Form 8-K under the Securities Exchange Act of 1934, as amended, as part of the Company's Form 8-K. We agree with the statements concerning our Firm in such Form 8-K. Very truly yours, /s/ Feldman Radin & Co., P.C. ------------------------------- Feldman Radin & Co., P.C.