If you are used to driving a petrol(?) estate, then a diesel van is going to sound pretty noisy in comparison, especially if there is no bulkhead. You can get petrol engined transit connect, i think it is a 1.8, and if you dont do a lot of miles, it might be worth looking for one. From what i have read on the transit forum, the 110bhp tdci is the best engine in terms of economy, not to mention power (always a bonus!), but i dont think there would be a huge difference between it and the 90bhp version. But if you are going diesel, make sure it is a tdci (that is the 90 and 110bhp versions) and not the 75bhp tddi (as well as being a slug, it is noisier and less efficient). But the connect is not especially economical in any guise compared to its rivals, so if you cover a lot of miles you might want to look at a vw caddy or citroen berlingo/peugeot partner. As for which version, as far as i am concerned, go for the lwb high roof, as even though you may not need the extra capacity over the swb now, you may decide to go for a bigger setup down the line and any difference in running costs will be tiny. For a 250l tank, you could use any version, but the 400l tank would be best in a 220 or 230. I have a lwb 230 tdci (90bhp) with a diy 500l setup. I have been using it for over 3.5 years now, it has served me well and never let me down (touchwood!). Average economy is 40mpg, and i drive pretty gently.