I have been very satisfied w/ the fit and quality of several sheets/blankets I got from "JUST FOR PONIES".
Winter before last, we had a night of -27 degrees, following a day w/ a HIGH temp of 0! I did blanket all but one of my minis; he had the longest, thickest coat of all and did fine. Two I shut into the barn(don't shut them in unless it is REALLY cold, but no need to 'invite' bitter cold air into my insulated barn by leaving stall doors open to runs in the COLDEST of weather, not to mention rain or snow falling!)I put 'regular' blankets on both overnight, and for several nights after, when temps were still quite cold. 'Outside' horses have a large, deep, southfacing run-in shed w/ their feeders against the back wall, for maximum protection against wind wind-driven rain/snow. My tiny mare got to wear a brand new, just-her-size, kevlar fleece-lined blanket I'd had for years, never used till then, and stayed snug and warm in it! Thank goodness, it was dry and not windy during that EXTREME cold snap, though, as wind and/or wetness would have made it MUCH worse!
Agree, use blankets ONLY when really needed-- healthy minis are especially well-suited for harsh weather conditions.
Margo