REL B3 and monitors vs full-range

I moved to a loft where my Dynaudio 1.3SEs sounded a little lost, and shopped around for a good pair of full-range speakers. It seemed like I would have to spend $6k to get the detail I like of the 1.3SE in something with loft-scale bass. In the end I just ended up adding a sub, a REL britannia B3. It's been six months and I'm still astonished when I listen. I don't really notice the sub directly, there's just way more there there. What am I missing with the monitors+sub combination that I'd have gotten with a good fullrange pair?
I do as you do most of the time, using monitors with a pair of REL Stadium subs. Lately I have been using my Spendor S 100s, which are a full range system and am still using the subs with them. I think you would have to go above $15000 [new] to get a speaker that gives an advantage over monitors and subs. There you would probably get a more coherent sound due to the system being simpler, however the main speakers would have to be quite large and might not work in a small room, it is easier to make the monitor/sub system work in these cases.
I went from Thiels CS7.2 full range speakers to Harbeth SHL5s & REL R505 sub. Been using this combo for almost a year now, and think I will be sticking with monitors/sub for quite awhile.
You have hit on a combination that is,evidently,great for your listening habits.Why bother with success?It takes some people years to find this.Just a thought.
The Rel will improve the sound in every application. Use it with full range speakers and set the crossover to 27 Hz or lower. Or use it set at 35 or wherevere you find works with your sats. It's real purpose is not to add more bass but to create the lowest bass that full range sPeakers don't do in a room. If you change just get an even better speaker that goes to 45Hz or so.