Yea I've used my split seat a couple of times in the 3 in the past year, but most times I don't bother because using the fold down seats involves removing a car seat.
In 2012, the Mazda 3 was still the best compact available. I don't regret my choice one bit. An extra oil change is not a huge issue really, although I noticed it in the last two years where I've only put 21,000km a year on the 3, an anomaly compared to the five years prior where I averaged 34,000km a year on the primary vehicle. I'm in a situation now where I'm doing my 72,000km/36 month service at 67,000km/34 months, due to the fact the first year we were doing oil changes by kms then the second and third year by months, so nothing's synchronized and it kinda irritates me.
Anyway, I'm not brand loyal, and the Accord offers more value. Although the Accord did drive too much like a big car when I test drove one, while the 6 felt perfect. Hm.