Are love to dream sleep suits suitable for a newborn. And are they safe for a baby when they are older?

There are many different types of swaddle suits, including the “love to dream”
Red Nose has the following information about swaddle suits.
“It is important to be aware that there is very limited evidence to support the use of specific products as devices to promote infant settling, back sleeping position and no evidence to support these products as a strategy to reduce the risk of infant death.
Red Nose recommends parents and care givers use lightweight wraps such as cotton or muslin”
https://rednose.org.au/article/safe-wrapping-or-swaddling-when-to-stop-and-how-to-select-a-safe-sleep-bag
Once baby rolls, it is important to cease swaddling/wrapping (including swaddle suits) - baby needs arms free to roll well.
Most babies are rolling by 4-5mths of age.
Not all swaddle suits can be modified to have “arms out”

https://rednose.org.au/article/what-do-we-do-now-that-a-baby-has-started-to-roll-over