If I lived in England I would not hesitate to get a Honda HRX537HZ.Also you have the striping Hondas , which are not available in the USA.

Thank you rosemallow for your advice. Unfortunately here, probably because of the sticky grass we have for most of the year, Hondas aren't known to be good baggers.

The HRX range is also very expensive whereas the Snapper model I referred to seems something of a bargain - if it works very well in both modes. This is what I'm trying to ascertain.

The trouble is I can't find a single user review on this side of the pond. Hence my post to GardenWeb.

The HRX in the USA is an excellent bagger. Some complaints are it actually can get top heavy from a super full bag. What does that tell you.
Just what type of grass is grown in the UK. In my area we have tall fescue.
Hondas are expensive here also, but it is worth it.

I don't know much about species and varieties of grass. I do know, for instance, that the original Izy range of Honda mowers were lousy at bagging when conditions were at all damp. (Remember that it's often wet here and grass has to be cut regardless).

The engineers at Honda brought out a new Izy range which, they claimed, had a redesigned chassis to overcome the problems but I haven't read any results yet.

There's a good forum here for landscape contractors and wet grass cutting is often discussed. The best mowers for that is a French firm called Etesia which will pick up well in all conditions. However, they don't do a roller striping model which is much lamented by the professionals. There are others as well.

So there are certainly excellent baggers here and good mulching mowers. What I'm after is a combination of the two and that is proving difficult in the face of no feedback from users.

Well, as for damp conditions all mowers have problems bagging and mulching when wet or damp.
The IZY has a redesigned high lift blade for bagging. The problem with wet or damp grass cuts the air flow in the bag. This makes it harder to fill it with grass. A bag with larger holes (material) would help, but then there is a danger of objects hitting the operator.
Anyway, I do not see a Snapper resolving your problem. I know nothing of the Etesia. Also stripping kits can be purchased for any mower.
Good Luck!

Just in case anyone is still reading this, I came across some useful information yesterday. A mower primarily designed for bagging cuts the grass once only. If then used for mulching, using a supplied mulching plug, presumably, it still cuts the grass once.

The whole idea of mulching is cut the grass more than once to reduce the clipping size. Therefore the combination mowers, as they are called here, are less efficient at mulching than at bagging.

Should have realised this myself.