I had my last van, VW Caddy, for 4 years, got LINE-X (exactly like speedliner) done when the system was installed by Ionics. Can't remember exactly how much it cost, think it was about £450.
When I came to sell the van, the floor was PERFECT. Not a single mark, honestly it looked like brand new. It had protected so well and that counted towards the re-sale price, so I would say it paid for itself easily. I'd highly recommend.
So, when I got my new van a year ago, I didn't hesitate, I got LINE-X again. It was a bit more expensive, about £550 I think (bigger van - Toyota Proace).
So my advice, get LINE-X and not only will it protect your floor amazingly well while you use your van, but when resale time comes it will probably pay for itself.