I haven't tried it in any over my current MLs but one i sold has no problem with shooting at least 5 shots of T7 without swabbing. My old WinAPex though was horrible with T7 no matter what i tried.

Most of us that are trying it are doing it out of curiosity of "what if" its better than the older powder. They probably don't recommend hotter charges due to some imports with a history of mediocre barrel quality. Many of those older extruded barrel guns are still in circulation. Some of them don't recommend over 100gr charges (loose powder) anyway or a max 100gr charge with a 300gr bullet. My old WinApex made be BPI even mentioned this in the manual. They suggested reducing charges by 10% with 300gr bullets.

Since we have no reviews, at this point this is all speculation as to how good or bad the new powder will be and why they impose such restrictions.