We love it! The 6-12 month size is a good, loose fit for our baby (she's 5 months, 7 kg). Glad we went for the next size up.
We've gotten so much use out of this romper. With the cooler weather my little girl wears it with leggings and a cardigan. The fabric is quite thin so it will be good for summer if it still fits.
The Isla romper is absolutely gorgeous. We were happy with all the clothes we ordered from Lulu Babe.