Honestly I would pick up the NExT as a great first implant, gives you the HF and LF so you have that.
Note that most access control is done using the UID of the tag so you will be able to do what you want with the storage on the implant.
The xEM side of the chip works great with the xAC for access control or other projects where as the xNT side works well with mobiles and has the ability to create records for your contact card or url.