We've only recently started seeing Norma powders in the UK after a gap of 15, maybe even 20 years in availability here. The surprising / interesting thing is how little the range has changed over the years.
When they were last here, I used the faster burners a lot - N200 / 201 and occasionally N202. They are excellent powders - nothing spectacular, but a combination of small grains and a bit of nitroglycerin content see them offer good velocities and 100% fill-ratios in many common cartridges.
Norma 203-B is Alliant Re15 under another name (albeit some of the SnipersHide people claim that Norma retains the 'best' lots for its own label and gives Alliant the rest

) and as it's now substantially cheaper in the UK than its Alliant equivalent, I advise people here to buy it instead as long as that condition lasts.
Likewise, it was said many years back that MRP and Re22 were one and the same thing. Current MRP users say it's better than Re22 nowadays - a little more flexible and can be pushed a bit more for higher MVs where needed / desired. They are certainly at the least
very close in their characteristics - compare maximum load charges and MVs and there is little difference.
I've recently bought N204 and a rare Norma addition to its range, URP, neither of which I've used previously and intend to do a side by side test against IMR and H4350 - both of which were banned from importation into the UK / Europe last year under new EU regulations. They look like potential good replacements for the very useful 4350 pair. URP alongside MRP has a relatively high nitroglycerin content at around 12% weight if memory serves - others are mostly in the single figures.
One potential downside especially for North American users, is that unlike Alliant's recent additions with its trademarked 'TZ' technology to control temperature sensitivity, I don't see any such signs in the Norma range even though many Alliant grades (including all 'TZ' types) and all Norma powders are made by the same people, Bofors in its Karlskoga, Sweden plant. It may be that Norma powders have been quietly upgraded in this regard (and like Vihtavuori) being modest Scandinavian types they've not shouted about product improvements. However, it's also possible that they are rather temperature affected. Norma does claim its relatively new URP is very temperature stable, but I for one have not seen any feedback on this.