Regarding the inefficiency of the SDB, keep in mind that the boilers on this machine are fairly small (950ml steam boiler and 300ml brew boiler). Some of the alternatives have larger boilers (A MaraX is 1800ml, a Puristika is 750ml). The Lelit Elisabeth has a smaller steam boiler though at 600ml (and 300ml brew boiler)
All in all, In your shoes, I’d keep the SDB as it is known to have good temperature stability, warms up quickly, and can at no (or very little) cost do pressure profiling. Even if milk drinks are not a priority, the fact that they can be done easily is a bonus.