The honest answer there is very little difference.
Cimilre and Spectra were born in South Korea in 1999 by Uzin Medicare and existed side by side until 2016 when Cimilre was spun-off into an independent manufacturer of leading baby care products.
In mid-2016 Cimilre launched its own electric breast pumps which whilst retaining their shared heritage with Spectra, made some adjustments and improvements to offer pumping mothers a better experience and offering then previously available.
So below you can see a comparison between the Cimilre S3 and the Spectra S2. The S3 is less than 2 years old and offers the absolute latest technology and design, whilst the S2 is very similar it is an older model which has been on the market for many years.
In Summary both Units are very similar, however with the latest design and technology the Cimilre S3 is a superior option as it has no disadvantagesbut has all the advantages of being;