Need to purchase new phones for our office and need some advice

Will need a four exec phones and others can be entry level.
Looking at the following GRANDSTREAM GXV3275 for myself simply cause it got Bluetooth inbuilt, YEALINK T42G, POLYCOM VVX 400 as exec level phones
and GRANDSTREAM GXP1628 as entry level phones..

Anyone have specific experience with these and how they provision with epygi 2x2.
The office does not have a techie and so want everything plug n play...