... the performer lid slides to the side on the performer, which can limit full/easy access to the full grate of food.
I have to humbly disagree with that assessment. I have a performer and have no problems with access to the full grate whatsoever. You don't even have to use the lid holder if you don't want to.
The Platinum, however, has a hidden issue with the lid design that most people overlook. The handle is mounted on the front and not the top like all the other kettles. Meaning you MUST slide the lid back and into the holder. This knocks you out of any possible add-ons such as a rotisserie, because it blocks the lid holder making it difficult, clumsy, & unsafe to remove/replace the lid otherwise.
I noticed this issue when we looked at different Weber models and was looking at the Stoven pellet grill attachment.
I think the performer is a much better option for the money. That big side table is awfully handy.
That's my 2ยข (not that it's worth that much
)