In the past I would agree that the Anthem was the closest match for the Allegro Bus, but for 2017 things have changed. The Aspire has been up-graded significantly. The new 2017 Aspires have many of the Anthem features now. Some of the upgrades in Aspire from 2016 to 2017 are independent front suspension, 17K front axles. The 2017 Aspire is now all-electric vs propane in 2016. Induction cooktop, other items too. There is now much less difference between an Aspire and an Anthem, so you could consider them BOTH to be an alternative to an Allegro Bus, depending on your budget.
See 2017 Entegra Changes
for a complete rundown of Entegra upgrades for 2017.