Well, I'm not sure what your goal/point is here? Like, what are you trying to accomplish?
i think the frontier is a great choice....possibly even better than the nauti for some people depending on vehicle/child, but since we personally already have a nauti we love, it isn't a choice for us...it seems to be a great value and long useage/expiration...
Also, I think that a booster is not always needed after the regent - if the kid is 9-10 with a 20 inch torso, I can see them going straight into a seat belt, so $279 + 0 = $279
i think you're right, it depends on what you want to do, whether the seats can be handed down, whether or not you want every last second of harnessing versus wanting more time in a booster, etc?
Obviously, the regent will harness the longest harnessed...but the frontier will hbb longer....and you probably dont want to buy BOTH of those...so you need to decide what trade off you are most comfortable with.
personally, in the few vehicles i have tried, the nauti belt guides go as high as is needed before the child would then fit into the seat belt properly. So for me, the equation is ...Nauti+ *nothing*
the nauti is the last seat i believe i will have to buy, it will last until dd is 9.5 as a harness or hbb, and then until 12.5 as a backless, so $150 + 0 = $150!
I guess for some reason you just don't like the nauti in booster mode? Or else you just love the monterey so much you have to have it??
With the seats currently available, if I had to plan for birth to seat belt for a child for the lowest cost but still respecting safety
Birth to 4 ish years - Scenera or AOE(intera, etc, any cheap 35 lb rfing convertible), to be used RFing until 35 pounds or height limit, which I expect to be between 3-4 years. (dd, 39 inches tall with a 15.5 inch torso, 3.5 yrs old, 35.5 pounds, can still fit RFing in the seat by height, she just exceeds weight limit,) and then FF if there is any FF room left.
When seat outgrown, purchase Nautilus, which will likely harness until at least age 6, probably 7 or 8...then use as hbb until expiration (about 9.5-10 yrs old if purchased new when child is 3.5-4 yrs old) then use as backless if still necesary until 12.5.
An infant seat can be added if infant does not fit into scenera or AOE at birth or parent desires it.
total cost, birth to seat belt, with the child being RF'ed to 35 lbs, and then harnessed until 65 or (18.5 torso) and boostered until seat belt-ready, is$40+ $150 = $190 OR $80 + $150 = $230
for 10 YEARS of cpsafety - $19-$23 per year, or about 40-50 cents a week.
With an added infant seat to fit the newborn stage, that increases the overal cost by about $50, so a complete total of $240-$280.