As far as a severum with your EBJD, a lot depends on whether it will be one year or two years imo, and to a degree what type of severum (rotkeils tend to stay slightly smaller than some other types ime, along the lines of 8+ inches compared to 10+ ). After a year if you have a 5 or 6 inch EBJD and 4-6 inch sev, not so bad if they get along together, but after two years if you have a 8 inch EBJD and 8,9 inch severum, both still with a little growing to do (just slower after that) it's going to be pretty tight.