Do you really need a barlow?

I don't own a barlow; don't see a need. Last night, I was viewing Jupiter with my 12.5 inch dobsonian (f/4.8) and was treated to some incredible views at 404x. This magnificaion was realized using a 3.8 Ultrascopic EP from Orion. The eye relief for this little fellow is more than comfortable for me and I suppose it is my "barlow." As far as the 50x per inch thingie, the nights are few for me which present good enough sky conditions to even push the magnification to the 400x level. But last night, I saw old Jupiter like I seldom have. The GRS was about the same color as the average cloud markings, yet the thin bordered outline it presented was astounding. Also, there was MUCH going on between the two major bands. A transit was also happening with Europa. Very satisfying. Switching to a 9mm Expanse EP, all of the aforementioned was still quite visible. Only smaller (duh!). Magnification isn't the most important ingredient for me in the mix leading to a truly satisifying and info packed observation. The prime ingredient is the overall condition of the sky at the moment.