Hi mhollas,
The adjustable bed thread here may be helpful and has some sources that you can use as a “value reference”.
In terms of personal experience I’ve owned a Reverie Deluxe for close to 3 years and have been very happy with it but the market, prices, and options available have changed since that time.
The weight limit for the Reverie Deluxe is apparently 600 lbs per unit (see post #13 here) although this is different from their warranty information here which says 300 lbs per side.
The weight limit for the Ergomotion 400 is 400 lbs per side for a split king.
The weight limit for the Prodigy is listed as 600 lbs per side in their owners manual but this was apparently not including the weight of the mattress so based on a several conversations with Richmond Bedding (click features and specs) who talk with L&P on a regular basis they changed it to 700 lbs including the mattress and the person together since Jan 1st of last year (2013) so they are now rating their adjustables consistently with how the other major manufacturers rate theirs.
All of these would probably work for your weight but the Reverie and the Prodigy have a higher capacity than the Ergomotion 400 so you would have a greater margin of safety.
Other than that … I would make your choice based on the features or options that are most important to you or that you would use the most vs the price of each because they are all durable and reliable choices IMO.
Phoenix