What you are asking about is a very personal decision. The mere mention of an iLock can be a very polarizing topic depending on who decides to chime into your thread .
Having said that I was in a similar situation as you .
I have the 2i4 and I also run the most current up to date version of SPlat...no Gobbler BTW...if that matters .
I held off w the iLock until last year and it was due to Focusrite offering some really nice plugs for free that I have finally bit and installed an i Lock on one of my computers ....
Some of the free plugs they were offering were just way out of my wallets comfort range and I wanted to get a feel for a few brands of musical tools & software that I was locked out of due to not having an iLock..
After having the i Lock installed for about a year on one computer , my impression and overall vibe is the i Lock seems to be working out for me so far ....I have no regrets .( still only on one computer )
After installing an i Lock I was able to go All Out Gung Ho and pick up some Krazy software deals on 3 rd party plugs and VST instruments from vendors that require the i Lock for activation ...
At some point I may go with the hardware dongle .
The truth is I'm in no rush ....
I don't know if my post is of any help to you ...anyway good luck too you in what ever you decide to do .
Kenny