Having played around with NIK Softwares HDR Efex Pro for a week or so, I decided to go ahead and buy a licence. I have Photomatix Pro 4.1 but found the ease of use of HDR Efex Pro and the photo-realistic results useful.
The Alignment and de-ghosting features are not perfect, but they can usually be coerced into producing a good render with a little bit of experimentation.
i.e. Sometime the Alignment option is best left off when images are already aligned (e.g. taken on a tripod) and even in NIK's own documentation they make reference to de-ghosting sometimes being better off than on.
Overall I am pleased with HDR Efex Pro and being a frequent user of their other great applications I find the interface powerful and familiar.