Welcome to the forum
@Roweman.
When all said and done, the Transporter is a small van, so the extra 40cm of a LWB will make a huge, positive difference to your camping experience - especially so with 2 dogs. It's the difference between having the floorspace to stand/ dress/ undress when the bed's out or not.
Some argue that a LWB is more tricky to park, but I've never had a problem parking mine, though my van is strictly a camper and isn't dailyed. IMO, the only valid reason for not going LWB is if you don't have room at home to park it - all other reasons are spurious... IMO.
Re engine choice, I wanted to avoid the potential drama and expense of a bi-turbo, so chose the 150. It provides more than adequate performance (for a camper) and is arguably the most robust engine in the lineup.
Re choice of conversion design and conversion company, that's purely down to your own personal taste and, of course, your budget. A bed on rails does provide more flexibility, but do at least consider a u-shaped setup, which provides great storage, a sociable space and a bigger bed, as long as you don't need to carry rear passengers.
HTH and happy hunting. Don't forget to post pics when you find the van of dreams!
