Heat press is one of those under appreciated tools.
We use ours from everything from heat transfer vinyl, did at one time do sublimation, bling transfers, apart of patch production (depends on if the customer wants adhesive backing or not in most instances) and applique production if I have to use the plotter to cut out the pieces, if it's hand cutting the applique pieces, then I don't need the heat press.
While I'm a huge, huge fan of Geo Knight, the biggest thing here is getting quality. "You" want constant and accurate heat across the platen(s) (if you have a bottom heated platen as well). That is going to be the biggest thing and as those no name presses age, that's harder and harder to get.
I would suggest swing away versus clam shell. Auto open is nice, but not a necessity. I do like having a digital readout on mine, including timer, but again that isn't necessary.