Precor, Octane and Life Fitness all make gym and home versions. Cybex makes an excellent and expensive gym version. Vision Fitness makes ellipticals for home use.
Cybex and Precor gym models are the gold standard because:
-Their models have proven durability in gym environments, and are the only ones with adjustable inclines. Variable incline is a significant feature in terms of intensity, that also serves to enable shifts in the primary muscles that can be targeted. Octane, Life Fitness and Vision do not have this feature, though Life Fitness does allow for variable stride length that IMO is an effective feature. Life Fitness is the only one of these three with significant gym use experience.
-All except Cybex make home versions that are well made and offer rigorous workouts using similar but slightly different elliptical motions. Only the Precor home version offers a variable incline. Life Fitness allows for variable stride length on some models, which is helpful.
-The Octane, Life Fitness and Vision have advantages in terms of space requirements. The Octane has the smallest footprint when in use. The Life Fitness and Vision have space advantages when they are folded up. In use, they require about the same approximate length as the Precor, which is the longest of the ellipticals.
Otherwise, they have similar motions with slight variations; all provide good workouts. Try each to see the difference in feel and intensity if this is important.
For something along the lines of 'Life but smaller, also consider Octane: