They go nicely hand in hand, i guess u like the messiness feelin from MDxx + speediness speed gives u. Thats why i drink a bit if i cant use molly with speed. Ive done GBL 3ml and speed. Its nice but be careful with dosage and do not consume any alcohol with it what so ever. Too much G and u mite end up sitting on ur ass the whole nite so easy with it. Just be safe about it.