As Electro Industries notes, their electric boilers have been considered "Standard of the Industry" for the past 20+ years. Radiant Design & Supply, Inc. uses Electro Industries boilers when the application is appropriate.
The "MS" or Midsize series boilers are also available from Radiant Design & Supply. Contact us with the form on our contact page to discuss whether these electric boilers are appropriate for your radiant heating needs. Here is the link to the Midsize boilers on the Electro Industries' website.
Here is a PDF file of product feature comparisons on Electro Industries' website - Boiler Model Comparisons.