I'd own one again, after all with all the traffic on the road you can't exactly go that fast the majority of the time.
Make sure it has pas as without it it's heavy, give it a good canning and then remove the expansion cap, it should hiss lightly, if it spews water everyway then the head might be cracked/hgf (which the latter doesn't happen often as they have a cast iron block and head).
Also when it's warm leave it running and pull the dipstick out, hopefully you shouldn't see any blow by gases/crank case compression due to blocked breather pipes, worn piston rings.
It should do ~45mpg and hit 95mph if you're lucky, rust is the killer of these vans, i swear they leave the factory with no to little undersealant causing V reg vans to be rusting already.
a lot of people on here will tell you they're crap and slow, yes they aren't going to beat many things of the lights (milk float, tractor ), but everyone has different views and standards, best thing is to go test drive it.