If your ramps have stops at the ends you shouldn't be able to drive off the end.

I don't trust axlestands, as they have narrow bases and are not really all
that stable...especially on soft ground.

I found a good set of homemade ramps secondhand,very cheap. They're really
heavy and would probably not slide on a concrete floor. They're also higher
than usual, which should make working anywhere underneath relatively easy.

I'd only work under a vehicle sitting on a jack if there was a really solid
item (say a section of treetrunk) there to take the weight if the jack
blows its seals. In fact you can jack the vehicle, insert the stump and
remove the jack. I did this a lot with my 57 back in the late 70s-early 80s
(still have that stump somewhere). It was also a great thing to use for
engine removals...slide under engine, loosen engine & pull stump out,
engine & all.

Andrew Grebneff
Dunedin, New Zealand
VW & mollusc nut
1984 Caravelle (currently SVX engine waiting for a trans)
1985 Mitsubishi Galant Sigma 2.0 (FWD)
1986 CE80 Toyota Corolla 1.8DX diesel
1989 CE96 Toyota Corolla 1.8DX diesel van/wagon
1989 CT170 Toyota Corona Select 2.0 diesel