I've had one of these for 3 years, also in 24" and use it for rough shooting.

Like you, I put two in the mag with nothing up the spout so I can walk around in safety and just pump it whilst coming up to the aim.

In terms of reliability, it has never missed a beat and even though it's been well used in all sorts of weather, the finish is still great as I clean and lube after every outing.

There are other pumps that have a huge following and better reputation for build quality, particularly over the pond, but I think the Hatsan Fieldhunter can hold it's own and represents excellent value for money.