I'm gonna go with an higher weight ERFing seat. Not only has ERFing shown more benefits than harnessing a very old child who can sit properly in a booster, but I just don't see the demand for that high of a weight harnessed seat. I truly think 95% of 100 lb children are fine and safe in a booster and do not need to be harnessed (nor would I want to lug that seat around or install it)
I don't see a huge demand for either, but I see less for that type of HWH seat. While EHing is gaining popularity, I really don't see anyone who does it much past 7-8 barring no medical problems. ANd the Regent is usually sufficient to get to that age group. The few that may need it past that should probably just get one of the special needs seats on the market.
I think ERFing will gain momento as the years go by and well, with our history of having larger taller heavier children in this Country
and a lot of kids outgrowing RFing much too early (like my kid), I think it would be wise to have a higher weight RFing seat. Because eventually even those huge 2 year olds do even out and are usually a normal weight and height by school age-thus not needing that extreme of a HWH seat, KWIM?
That totally didn't make any sense LOL