IpSec and iscsi target

[MarcoP]

I know moderators will hate this post as discussed many times already but I need to understand the cons, apologies.
I wont talk about samba, M$ sharing and others, my main interest is in iSCSI target using ipSec tunnel only.

I do already have a dedicated 750GiB Raid5 NFS iSCSI NAS and soon its going to be a 4TB, just you know I'm not after any debate on what should be used or not. I still prefer to use a dedicated box but sometimes I wish I could use something basic.

There is an iSCSI target port for NetBSD and pfSense supports ipSec and Posix, Mac and Windows comes with iSCSI initiators already.

What's the disadvantages or risks when using iSCSI with IP filtering and password protected logins inside a ipSec tunnel when installed on the same box as pfSense?

Is it just a risk or there are known issues?

Any ideas?