Short answer: yes. MIDI Designer Lite unlocked is identical to Pro.
The only differences is that the Pro Unlock can be purchased for just iPad and/or just iPhone/iPod touch. Buying MIDI Designer Pro gives you both devices for a minimal discount (less than one US dollar at present).
In terms of functionality, release cycles and support, an unlocked version of Lite is identical to Pro in every way.
The Pro icon is slightly different.