Anyone building McCarthy or GJ Gardener acreage homes

Has anyone built or is building an acreage home? I am currently looking at the Ruralview or the Windermere from McCarthy Homes, or the GJ Gardener's acreage choices (Montville or the Kingaroy). Have you had good/bad experiences? Do they stick to time budgets? Any hidden extras? I would be building in the Greenbank area in south Brisbane.

I know of a very good custom builder whom I am in the process of dealing with who has several acreage style plans. Besides my Uncles canal house I had a look through 2 other houses on acreage before making my decision. So far the experience has been brilliant and the guy we are dealing with has been spot on. It's only us and our bank holding up the process now. Their costing is on par with most of the other majors and I believe they've built a few out in your area aswell. PM me if you want details.